UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of The

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

October 12, 2011

ProShares Trust II

(Exact name of registrant as specified in its charter)

Michael L. Sapir

c/o ProShare Capital Management LLC

7501 Wisconsin Avenue

Suite 1000

Bethesda, Maryland 20814

(240) 497-6400

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Anthony A. Lopez III, Esq.

c/o Clifford Chance US LLP

31 West 52nd Street

New York, New York 10019

and

Amy R. Doberman

c/o ProShare Capital Management LLC

7501 Wisconsin Avenue

Suite 1000

Bethesda, MD 20814

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

On September 27, 2011, ProShares Trust II issued a press release announcing a stock split (the “Split”) on one of its series, ProShares UltraSilver, and a reverse stock split (the “Reverse Split”) on one of its series, ProShares UltraShort Yen. The Split and the Reverse Split will not change the value of a shareholder’s investment.

The Split will split shares 2-for-1 and apply to shareholders of record as of the close of the markets on October 10, 2011, payable after the close of the markets on October 12, 2011. ProShares UltraSilver (NYSE Arca symbol “ACQ”) will trade at its post-split price on October 13, 2011. The ticker symbol and CUSIP number for the fund will not change.

The Split will decrease the price per share of the fund with a proportionate increase in the number of shares outstanding. For example, for a 2-for-1 split, every pre-split share held by a shareholder will result in the receipt of two post-split shares, which will be priced at half of the net asset value (“NAV”) of a pre-split share.

The Reverse Split will reverse split shares 1-for-3 and apply to shareholders of record as of the close of the markets on October 12, 2011. ProShares UltraShort Yen (NYSE Arca symbol “YCS”) will trade at its post-split price on October 13, 2011. The ticker symbol for the fund will not change but the fund will be issued a new CUSIP number, 74347W569.

The Reverse Split will increase the price per share of the fund with a proportionate decrease in the number of shares outstanding. For example, for a 1-for-3 reverse split, every three pre-split shares held by a shareholder will result in the receipt of one post-split share, which will be priced three times higher than the NAV of a pre-split share.

For shareholders who hold quantities of shares that are not an exact multiple of the reverse split ratio (for example, not a multiple of 3 for a 1-to-3 reverse split), the reverse split will result in the creation of a fractional share. Post-reverse split fractional shares will be redeemed for cash and sent to the shareholder’s broker of record. This redemption may cause some shareholders to realize gains or losses, which could be a taxable event for those shareholders.

(d) Exhibits

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: October 12, 2011