A straphanger was stabbed on a Manhattan train Friday afternoon, cops said.

The attack happened just after 1 p.m. on a northbound 4 train, police said.

The unidentified victim was stabbed in the belly during an argument with another man while the train was stopped at 125th Street and Lexington Avenue, police said.

The attacker fled the scene before the doors closed at the 125th Street station. The victim was taken to Lincoln Medical Center with non-life threatening injuries.