PAO Powershares Riverfront Tactical Balanced Growth Portfolio

AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON MAY 23, 2008.

No. 333-102228

No. 811-21265

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM N-1A

(Check appropriate box or boxes)

POWERSHARES EXCHANGE-TRADED FUND TRUST

(Exact Name of Registrant as Specified in Charter)

301 West Roosevelt Road

Wheaton, IL 60187

(Address of Principal Executive Office)

Registrant’s Telephone Number, including Area Code:  (800) 983-0903

APPROXIMATE DATE OF PROPOSED PUBLIC OFFERING:

It is proposed that this filing will become effective (check appropriate box)

o             immediately upon filing pursuant to paragraph (b) of Rule 485.

x            on June 20, 2008 pursuant to paragraph (b) of Rule 485.

o             60 days after filing pursuant to paragraph (a)(1) of Rule 485.

o             on [date] pursuant to paragraph (a) of Rule 485.

o             75 days after filing pursuant to paragraph (a)(2) of Rule 485.

o             on [date] pursuant to paragraph (a) of Rule 485.

The sole purpose of this filing is to delay the effectiveness of the Trust’s  Post-Effective Amendment No. 81 to its Registration Statement until June 20, 2008. Post-Effective Amendment No. 81 to the Trust’s Registration Statement relates to the PowerShares Dynamic Brand Name Products Portfolio, which was created pursuant to Post-Effective Amendment No. 17 to the Trust’s Registration Statement filed on December 3, 2004.  The effectiveness of the Registration Statement was delayed pursuant to Post-Effective Amendment Nos. 19, 21, 23, 24, 25, 27, 30, 31, 33, 34, 36, 37, 39, 41, 44, 46, 47, 48, 51, 56, 59, 63, 65, 67, 69, 70, 71, 72, 74, 76, 77, 78, 80, 81, 90, 98, 103, 105, 108, 111, 116, 119, 122, 127, 128, 131, 134, 138, 142, 145, 148, 156, 158, 163, 167, 172 and 178 to the Trust’s Registration Statement filed on February 23, 2005, February 25, 2005, March 24, 2005, April 22, 2005, May 6, 2005, May 13, 2005, June 10, 2005, June 22, 2005, June 23, 2005, July 11, 2005, July 25, 2005, August 8, 2005, August 22, 2005, August 25, 2005, August 29, 2005, September 12, 2005, September 13, 2005, September 14, 2005, September 30, 2005, October 25, 2005, November 18, 2005, December 2, 2005, December 29, 2005, January 27, 2006, February 24, 2006, March 24, 2006, April 21, 2006, May 19, 2006, June 16, 2006, July 14, 2006, July 21, 2006, July 28, 2006, August 4, 2006, August 11, 2006, October 10, 2006, November 9, 2006, December 1, 2006, December 20, 2006, January 10, 2007, January 31, 2007, February 20, 2007, March 20, 2007, April 19, 2007, May 18, 2007, June 15, 2007, July 13, 2007, August 10, 2007, September 10, 2007, October 10, 2007, November 9, 2007, December 7, 2007, January 4, 2008, January 14, 2008, February 4, 2008, February 29, 2008, March 28, 2008 and April 25, 2008, respectively. Parts A, B and C of Registrant’s Post-Effective Amendment No. 158 under the Securities Act of 1933 and Amendment No. 160 under the Investment  Company Act of 1940, filed on January 14, 2008, are incorporated by reference herein.

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SIGNATURES

Pursuant to the requirements of the Securities Act and the Investment Company Act, the Fund certifies that it meets all of the requirements for effectiveness of this registration statement under Rule 485(b) under the Securities Act and has duly caused this registration statement to be signed on its behalf by the undersigned, duly authorized, in the City of Wheaton and State of Illinois, on the 23rd day of May, 2008.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed below by the following persons in the capacities indicated on the dates indicated.

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