It’s enough to make your skin crawl.

A dead homeless man was found covered in bed bugs on an uptown D train Tuesday night, according to police sources.

Straphangers reported the grisly discovery and alerted police when the train pulled into Manhattan’s 59th Street-Columbus Circle station around 8:40 p.m., sources said.

The man was pronounced dead on the scene, sources said. It was unclear how long he had been dead.

Police are trying to identify the man, who is believed to be in his 40s, and they did not expect foul play.

The medical examiner will determine the cause of death.

The death was reported the same day the city released data on its six-month-old program aimed at getting homeless subway dwellers into shelters. The project has only experienced a 36.8 percent take-up rate, according to the city.

Reports of dead bodies on the trains typically increase during the winter when more homeless New Yorkers head underground, the union representing transit workers told the Post.

Nelson Rivera, administrative vice president for the union, Transport Workers Union Local 100, said the city has been failing to adequately address the homeless crisis, leaving workers and riders to deal with occasionally “traumatizing” discoveries.

“It’s a sad situation — every winter this is prevalent because you have people seeking shelter on the trains,” Rivera said. “But the police come to take these people and there are no resources and nowhere to take them. They get bounced around.”

A rider had first flagged the D train’s conductor about the body, who then called in the corpse to the MTA’s Rail Control Center, according to a union source.

At that point, it wasn’t clear if the person was still alive.

“The conductor said he couldn’t tell — and he wasn’t going to touch him,” the source said.