A man who urinated on a Queens subway platform early Saturday shoved a cop who tried to cuff him — and another officer fell down the stairs as he tried to pursue the offender, police said.

Cops caught 30-year-old Roger Barksdale in the act as he relieved himself inside the Rockaway Boulevard A train station in Ozone Park around midnight and tried to arrest him.

Barksdale resisted, pushing one of the cops before he bolted, police said.

A second officer who tried to chase Barksdale fell down the station’s steps, injuring his right knee, cops said.

He was taken to a local hospital in stable condition. The other officer refused medical attention on scene.

Barksdale was still on the loose Saturday.