UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K/A

Amendment No. 2

or

Commission file number: 001-34200

PROSHARES TRUST II

(Exact name of registrant as specified in its charter)

c/o ProShare Capital Management LLC

7501 Wisconsin Avenue, Suite 1000

Bethesda, Maryland 20814

(Address of principal executive offices) (Zip Code)

(240) 497-6400

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    x  Yes    ¨  No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    ¨  Yes    x  No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    x  Yes    ¨  No

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    x  Yes    ¨  No

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  x

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act.).    ¨  Yes    x  No

The aggregate market value of the ProShares Ultra DJ-UBS Commodity Fund’s units held by non-affiliates as of June 30, 2010 was $12,188,000. The ProShares Ultra DJ-UBS Commodity Fund had 550,014 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares UltraShort DJ-UBS Commodity Fund’s units held by non-affiliates as of June 30, 2010 was $3,402,000. The ProShares UltraShort DJ-UBS Commodity Fund had 60,003 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares Ultra DJ-UBS Crude Oil Fund’s units held by non-affiliates as of June 30, 2010 was $496,036,500. The ProShares Ultra DJ-UBS Crude Oil Fund had 9,900,004 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares UltraShort DJ-UBS Crude Oil Fund’s units held by non-affiliates as of June 30, 2010 was $51,816,000. The ProShares UltraShort DJ-UBS Crude Oil Fund had 1,870,003 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares Short DJ-UBS Natural Gas Fund’s units held by non-affiliates as of June 30, 2010 was $0. The ProShares Short DJ-UBS Natural Gas Fund had 4 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares Ultra Gold Fund’s units held by non-affiliates as of June 30, 2010 was $209,362,500. The ProShares Ultra Gold Fund had 3,450,014 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares Short Gold Fund’s units held by non-affiliates as of June 30, 2010 was $0. The ProShares Short Gold Fund had 4 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares UltraShort Gold Fund’s units held by non-affiliates as of June 30, 2010 was $71,721,629. The ProShares UltraShort Gold Fund had 3,639,901 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares Ultra Silver Fund’s units held by non-affiliates as of June 30, 2010 was $178,609,500. The ProShares Ultra Silver Fund had 3,950,014 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares UltraShort Silver Fund’s units held by non-affiliates as of June 30, 2010 was $61,021,976. The ProShares UltraShort Silver Fund had 4,294,979 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares Ultra Euro Fund’s units held by non-affiliates as of June 30, 2010 was $16,320,000. The ProShares Ultra Euro Fund had 300,014 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares UltraShort Euro Fund’s units held by non-affiliates as of June 30, 2010 was $462,685,000. The ProShares UltraShort Euro Fund had 22,850,014 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares Ultra Yen Fund’s units held by non-affiliates as of June 30, 2010 was $4,297,500. The ProShares Ultra Yen Fund had 100,014 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares UltraShort Yen Fund’s units held by non-affiliates as of June 30, 2010 was $145,068,000. The ProShares UltraShort Yen Fund had 20,000,014 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares VIX Short-Term Futures Fund’s units held by non-affiliates as of June 30, 2010 was $0. The ProShares VIX Short-Term Futures Fund had 175,005 outstanding units as of February 25, 2011.

The aggregate market value of the ProShares VIX Mid-Term Futures Fund’s units held by non-affiliates as of June 30, 2010 was $0. The ProShares VIX Mid-Term Futures Fund had 100,005 outstanding units as of February 25, 2011.

DOCUMENTS INCORPORATED BY REFERENCE:

None.

THE FINANCIAL STATEMENT SCHEDULES CONTAINED IN PART IV OF THIS ANNUAL REPORT ON FORM 10-K CONSTITUTE THE ANNUAL REPORT WITH RESPECT TO THE COMMODITY POOLS FOR PURPOSES OF COMMODITY FUTURES TRADING COMMISSION RULE 4.22(C)

EXPLANATORY NOTE

This Amendment No. 2 to the Annual Report on Form 10-K for the fiscal year ended December 31, 2010 of ProShares Trust II (the “Trust”), filed with the U.S. Securities and Exchange Commission on March 1, 2011 (the “Form 10-K”), as amended by Amendment No. 1 to the Form 10-K, is being filed to amend Part II, “Item 8. Financial Statements and Supplementary Data” of the Form 10-K to clarify that the “Report of Independent Registered Public Accounting Firm” addresses the financial statements and internal control over financial reporting of the combined Trust and each of the individual sixteen funds. This Amendment No. 2 also further amends Part II, “Item 9A. Controls and Procedures” of the Form 10-K to: (a) reflect that the Trust’s management has evaluated the disclosure controls and procedures both for the individual funds and the Trust taken as a whole and to include the conclusions of such evaluations, and to make conforming changes to “Management’s Annual Report on Internal Control Over Financial Reporting”; (b) reflect that there were no changes in the Trust’s or the funds’ internal control over financial reporting that occurred during the quarter ended December 31, 2010 that have materially affected, or are reasonably likely to materially affect, the Trust’s or the funds’ internal control over financial reporting; and (c) clarify that the scope of the Trust’s certifications applies both to the individual funds and to the Trust taken as a whole, and that the Principal Executive Officer and Principal Financial Officer are certifying both as to each fund and the Trust taken as a whole.

Except as set forth above, no other changes have been made to the Form 10-K, and this Amendment No. 2 does not amend, update or change any other items or disclosure found in the Form 10-K. Further, this Amendment No. 2 does not reflect events that may have occurred after the filing of the Form 10-K.

Part II

Item 8. Financial Statements and Supplementary Data

Statement of Operations for three month periods ended March 31, 2010, June 30, 2010, September 30, 2010, December 31, 2010, the year ended December 31, 2010, the three month periods ended March 31, 2009, June 30, 2009, September 30, 2009, December 31, 2009 and the year ended December 31, 2009 for each Fund.

PROSHARES ULTRA DJ-UBS COMMODITY

1

PROSHARES ULTRA DJ-UBS CRUDE OIL

2

PROSHARES ULTRA GOLD

3

PROSHARES ULTRA SILVER

4

PROSHARES ULTRA EURO

5

PROSHARES ULTRA YEN

See the Index to Financial Statements on Page F-1 for a list of the financial statements being filed as part of this Annual Report on Form 10-K. Those Financial Statements, and the notes and schedules related thereto, are incorporated by reference into this Item 8.

6

Item 9A. Controls and Procedures.

Disclosure Controls and Procedures

Under the supervision and with the participation of the principal executive officer and principal financial officer of the Trust, Trust management has evaluated the effectiveness of the Trust’s and the Funds’ disclosure controls and procedures, and have concluded that the disclosure controls and procedures of the Trust and the Funds (as defined in Rule 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended) were effective, as of December 31, 2010, to provide reasonable assurance that information required to be disclosed in the reports that the Trust files or submits under the 1934 Act on behalf of itself and the Funds is recorded, processed, summarized and reported, within the time periods specified in the applicable rules and forms, and that it is accumulated and communicated to the duly authorized officers of the Trust as appropriate to allow timely decisions regarding required disclosure.

Management’s Annual Report on Internal Control Over Financial Reporting

The Trust’s Management takes responsibility for establishing and maintaining adequate internal control over financial reporting of the Trust and the Funds, as defined in 1934 Act Rules 13a-15(f) and 15d-15(f). The Trust’s and the Funds’ internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with accounting principles generally accepted in the United States of America. Internal control over financial reporting includes those policies and procedures that: (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the Trust and the Funds; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that the Trust’s and the Funds’ receipts and expenditures are being made only in accordance with appropriate authorizations of management of the Trust on behalf of the Trust and the Funds; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the Trust’s or the Funds’ assets that could have a material effect on the Trust’s or the Funds’ financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

The principal executive officer and principal financial officer of the Trust assessed the effectiveness of the Trust’s and the Funds’ internal control over financial reporting as of December 31, 2010. Their assessment included an evaluation of the design of the Trust’s and the Funds’ internal control over financial reporting and testing of the operational effectiveness of their internal control over financial reporting. In making its assessment, the Trust’s management has utilized the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in its report entitled Internal Control – Integrated Framework. Based on their assessment and those criteria, the principal executive officer and principal financial officer of the Trust concluded that the Trust’s and the Funds’ internal control over financial reporting was effective as of December 31, 2010.

The effectiveness of the Trust’s and the Funds’ internal control over financial reporting as of December 31, 2010 has been audited by PricewaterhouseCoopers LLP, the independent registered public accounting firm, as stated in their report which is included herein.

7

Changes in Internal Control over Financial Reporting

There were no changes in the Trust’s or the Funds’ internal control over financial reporting that occurred during the quarter ended December 31, 2010 that have materially affected, or are reasonably likely to materially affect, the Trust’s or the Funds’ internal control over financial reporting.

Certifications

The certifications by the Principal Executive Officer and Principal Financial Officer of the Trust required by Section 302 and Section 906 of the Sarbanes-Oxley Act of 2002, which are filed or furnished as exhibits to this Annual Report on Form 10-K, apply both to the Trust taken as a whole and each Fund, and the Principal Executive Officer and Principal Financial Officer of the Trust are certifying both as to the Trust taken as a whole and each Fund.

8

Exhibit Index

Part IV

Financial Statement Schedules

See the Index to Financial Statements on Page F-1 for a list of the financial statements being filed as part of this Annual Report on Form 10-K/A. Schedules may have been omitted since they are either not required, not applicable, or the information has otherwise been included.

ProShares Trust II

Financial Statements as of December 31, 2010

Index

F-1

Report of Independent Registered Public Accounting Firm

To the Shareholders of ProShares Trust II:

In our opinion, the accompanying combined and individual statements of financial condition and the related combined and individual statements of operations, of changes in shareholders’ equity and of cash flows present fairly, in all material respects, the combined financial position of the ProShares Trust II and the individual financial positions of each of the following sixteen funds comprising the ProShares Trust II:

(collectively, the “Trust”) at December 31, 2010 and December 31, 2009, and the combined and individual results of their operations and their combined and individual cash flows for the years ended December 31, 2010 and December 31, 2009 and the period from August 6, 2008 (Inception) through December 31, 2008 in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the combined Trust and each of the individual funds maintained, in all material respects, effective internal control over financial reporting as of December 31, 2010, based on criteria established in Internal Control - Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). The Trust’s management is responsible for these financial statements, for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in Management’s Annual Report on Internal Control Over Financial Reporting appearing under Item 9A. Our responsibility is to express opinions on the combined Trust and each of the individual fund financial statements and on the combined Trust’s and each of the individual fund’s internal control over financial reporting based on our audits (which were integrated audits in 2010 and 2009). We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement and whether effective internal control over financial reporting was maintained in all material respects. Our audits of the financial statements included examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.

A trust’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A trust’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the trust; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the trust are being made only in accordance with authorizations of management and directors of the trust; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the trust’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ PricewaterhouseCoopers LLP

Columbus, Ohio

February 28, 2011

F-2

PROSHARES ULTRA DJ-UBS COMMODITY

STATEMENTS OF FINANCIAL CONDITION