Prospectus Supplement No. 6		Filed Pursuant to Rule 424(b)(3) and Rule 424(b)(7)
(To Prospectus dated August 22, 2006)		Registration Number 333-136819

$143,750,000

QUANTA SERVICES, INC.

3.75% Convertible Subordinated Notes Due 2026
and the Common Stock Issuable Upon Conversion of the Notes

     This prospectus supplement relates to the resale by selling security holders of our 3.75% Convertible Subordinated Notes Due 2026 and the shares of our common stock issuable upon conversion of the notes.

     This prospectus supplement should be read in conjunction with, and may not be delivered or utilized without, the original prospectus dated August 22, 2006, Supplement No. 1 to such prospectus dated August 31, 2006, Supplement No. 2 to such prospectus dated September 14, 2006, Supplement No. 3 to such prospectus dated September 28, 2006, Supplement No. 4 to such prospectus dated November 1, 2006 and Supplement No. 5 to such prospectus dated January 11, 2007. The terms of the notes are set forth in the original prospectus.

Investing in these securities involves risks. See “Risk Factors” beginning on page 10 of the prospectus.

     Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the notes or the shares of common stock issuable upon conversion of the notes or determined if the prospectus or this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is January 31, 2007.

SELLING SECURITY HOLDERS

     The information in the table appearing under the heading “Selling Security Holders” in the prospectus is amended by adding the information below with respect to persons not previously listed in the prospectus and by supplementing the information with respect to other persons previously listed in the prospectus that are listed below. This information was furnished to us by the selling security holders listed below on or before January 30, 2007.

     Based on information provided by the selling security holders, none of the selling security holders has held any position or office or has had any material relationship with us within the past three years.

										Shares of								Shares of
		Principal								Common								Common
		Amount of								Stock								Stock
		Notes								Beneficially				Shares of				Beneficially				Percentage
		Beneficially				Percentage				Owned				Common				Owned				of Common
		Owned and				of Notes				Prior to				Stock				After				Stock
Name		Offered				Outstanding				Offering				Offered				Offering				Outstanding
CBI Pension(1)		$	35,000				*				1,562				1,562				—				—
Celanese Americas Corp Retire Pension(1)		$	250,000				*				11,156				11,156				—				—
Cervantes Portfolio LLC(1)		$	300,000				*				13,387				13,387				—				—
Earlham College Endowment(1)		$	150,000				*				6,694				6,694				—				—
Fairfax County Employees’ Retirement(1)		$	300,000				*				13,387				13,387				—				—
Kellogg Co. — Master Retirement Trust(1)		$	500,000				*				22,312				22,312				—				—
Kellogg Co. — Welfare Benefit Trust(1)		$	200,000				*				8,925				8,925				—				—
Pension Reserves Investment Trust Fund(1)		$	2,000,000				1.39	%			89,246				89,246				—				—
Praxair Retirement Program(1)		$	190,000				*				8,479				8,479				—				—
Reform Pension Board(1)		$	175,000				*				7,810				7,810				—				—
RI Employees’ Retirement System(1)		$	250,000				*				11,156				11,156				—				—
Rockwell Automation Master Trust(1)		$	175,000				*				7,810				7,810				—				—
Southwest Carpenters Pension Trust(1)		$	300,000				*				13,387				13,387				—				—
Teachers Retirement System of Louisiana(1)		$	1,000,000				*				44,623				44,623				—				—
University of Southern California(1)		$	225,000				*				10,041				10,041				—				—
Wyeth Retirement Plan-U.S. Master Trust(1)		$	500,000				*				22,312				22,312				—				—