A hammer-swinging weirdo threatened to “rearrange your face” after he stalked a straphanger through a Manhattan subway station on Wednesday, police said.

The 28-year-old victim was on the L train at Union Square on his way to work at about 7:15 a.m. when he felt someone grope him, he said in an online post.

“He [told] me I have a nice ass,” the victim wrote.

The creep followed him through the station, then onto another train. When the victim tried to give him the slip by hopping off the train and catching the next one, the man kept tailing him, he said.

“He comes up to me and I confront him saying ‘look man you gotta stop following me.'”

The perv followed him off the train at 96th Street and above ground, where he ran up to the victim on Park Avenue near 97th Street, brandishing the huge hammer.

That’s when the deranged man started threatening to kill him and promising to find him after work.

“I’ll rearrange your face,” the crazed man told him, according to police.

The bizarre assault comes just a few weeks after another hammer-wielding maniac swung at a straphanger on a subway platform in the Bronx and yelled homophobic slurs.

Police do not currently believe the two incidents are connected, authorities said.