Form: 10-K/A

Annual report pursuant to Section 13 and 15(d)

May 31, 2013

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statements on Form S-8 (Nos. 333-47069, 333-56849, 333-103570, 333-143923, 333-142279, 333-174306 and 333-174374) and Form S-3 (Nos. 333-81419, 333-90961, 333-114938 and 333-119134) of Quanta Services, Inc. of our report dated March 1, 2013 relating to the financial statements and the effectiveness of internal control over financial reporting, which appears in this Form 10-K, as amended.

/s/ PricewaterhouseCoopers LLP

Houston, Texas

May 31, 2013