A Harlem man says transit cops framed him as a pervert in a “pee pee” sting, according to a new lawsuit.

William Campbell says in court papers that he was relieving himself in a men’s restroom at Grand Central Terminal at 10:40 p.m. April 16, 2017, when the incident went down.

A man in the next urinal “leaned over and looked at [his] penis,” according to Campbell’s Manhattan Supreme Court suit.

“As the man leaned closer to [Campbell], [Campbell] pushed him away,” the suit says.

Next thing Campbell knew, an MTA police officer “jumped” on him and said “What are you doing you, f—ing faggot?” and called him a “dirty homo,” according to court papers.

As Campbell was being led away in handcuffs, the cop yelled to a fellow officer, “Another pee pee case,” the suit says.

Campbell was charged with indecent exposure and other raps. The charges were later dropped.

He’s suing for false arrest and seeking unspecified damages.

An MTA spokesman said, “We cannot comment on the specifics of this case or any pending litigation. MTA Police officers are vital to maintaining a safe environment for Metro-North customers and all who visit Grand Central.”