Woodall added eight assists for the Panthers (3-0), who will play Michigan in the tournament semifinals next week.
Pitt kept Lehigh's C.J. McCollum in check for most of the night. The senior preseason All-American finished with 17 points on 7-of-11 shooting but was a nonfactor when Pitt broke it open.
The Mountain Hawks (1-2) hung tough during the first half but had no answer during a 21-5 burst by Pitt early in the second half. Zanna scored seven straight points during the run while Woodall sandwiched layups around a basket by Steven Adams as Pitt turned a 35-32 lead into a comfortable 56-37 cushion.
Lehigh, which upset Duke in last year's NCAA tournament, shot just 32 percent in the second half.
The Panthers are looking to erase the memory of last season, when they endured the worst year of coach Jamie Dixon's tenure. Pitt missed the NCAA tournament for the first time in over a decade and lacked the kind of typical offensive efficiency that's been one of the program's hallmarks under Dixon.
Those issues appear to have disappeared.
Dixon's decision to start freshman James Robinson at point guard has taken some of the pressure off Woodall to do everything and allowed him to play with more freedom. The fifth-year senior is thriving and so are the Panthers.
Pitt had 17 assists on its 29 baskets and outscored Lehigh 36-12 in the paint, many of them layups for big guys like Zanna and Steven Adams created by Woodall.
Woodall fed Adams for a dunk during the game-turning run that pushed Pitt's lead to double digits. He added a 3-pointer a minute later then pump faked, drew a defender and fed Zanna for another easy basket.
The Mountain Hawks simply couldn't keep up. Gabe Knutson added 12 points but Lehigh was outrebounded 38-22 and had just five assists while turning it over 15 times. Coach Brett Reed exhausted his timeouts during Pitt's surge, but it did little to slow down the Panthers.
Pitt -- which struggled at home last season -- had little trouble the rest of the way against one of the country's better mid-major programs.
The Mountain Hawks stunned second-seeded Duke in the NCAA tournament last spring and have one of the best guards in the country in McCollum, who bypassed on the NBA to help raise his draft stock and guide Lehigh to another Patriot League title.
McCollum wasted little time asserting himself, scoring Lehigh's first five points, though he had plenty of help during a back-and-forth first half that featured nine lead changes and six ties. Pitt eventually moved in front 35-30 at the break on the strength of the quickly improving Zanna, who has emerged as the Panthers' top big man early in the season.
Slipping into open spaces and being assertive with the ball in his hands, Zanna exploited his size advantage to overwhelm the undersized Mountain Hawks in the lane.
Follow Will Graves at www.twitter.com/WillGravesAP