A panhandler slashed a man on board a Manhattan train early Monday, authorities said. 

The 32-year-old victim was riding a No. 1 train approaching 103rd Street on the Upper West Side around 3 a.m. when the suspect approached him and demanded money, police said. 

When the victim refused, the mugger slashed him on the left hand and thigh, cops said. 

The suspect grabbed $40 from the victim, but didn’t get off the train until two stops later at 125th Street in Harlem, police said. 

The victim got off the train at the next stop,137th Street, where he reported the crime, cops said. 

He was taken to Harlem Hospital, where he was listed in stable condition. 

The incident comes days after three teenagers — one of them wielding a boxcutter — beat and robbed a man at a Bronx subway station early Friday. 

Thursday morning, a woman was choked during a mugging in Penn Station and a man was pummeled by a backpack thief on a Bronx train.