O'Brien recorded a 40-35 mark during his time at North Carolina State, going 22-26 within the Atlantic Coast Conference -- including 1-14 on the road against ACC foes.
"Coach O'Brien's service to N.C. State over the last six years has been sincerely appreciated by Wolfpack Nation," Yow said in a statement. "We especially appreciate his attention toward NCAA rules compliance, a value that will continue to be held by N.C. State. We wish him well in future pursuits."
The Wolfpack went 7-5 under O'Brien in the recently completed season. His best year was 2010, when the squad went 9-4 with a win over West Virginia in the Champs Sports Bowl.
"I appreciate the opportunity to have coached at North Carolina State University and I feel that the program is in a better place now than when I started," O'Brien said.
Offensive coordinator Dana Bible will serve as interim head coach for the Wolfpack's upcoming bowl game, Yow said.