Two people told The Associated Press that they each were told by a senior administration official that chief of staff Bill Ward is leaving the job.
The people spoke on condition of anonymity because they didn't want to be named divulging private conversations.
Corbett spokesman Kevin Harley said Thursday he couldn't comment on questions about Ward, a former prosecutor and longtime friend of Corbett's from Pittsburgh.
Corbett, a Republican, is battling Democrats over a cost-cutting agenda that's hitting public schools, universities and the poor while he cuts business taxes and grapples with rising pension costs.
Meanwhile, the Corbett administration is viewed as politically clumsy by many Republican lawmakers, and he angered conservatives with his endorsement in the crowded U.S. Senate primary.