The father of an on-the-lam suspect in Monday’s deadly shooting at Penn Station has a message for his son: Turn yourself in.

Police want to question Vincent Arcona, 27, about the gunfight that left one man dead and another critically wounded outside the turnstiles of the West 35th Street and Eighth Avenue subway station at around 6 a.m. on Monday, cops said.

“He should turn himself in,” said the dad, Paul Arcona, 50. “That’s it.”

The suspect has been an addict since he was a teen, Paul Arcona said, claiming Vincent told him that he was booted from a rehab facility on Friday when his Medicaid coverage ran out.

“Whatever medication he was on, he’s having a problem with it,” the elder Arcona said. “He wasn’t stable and he hasn’t been for a long time.”

Vincent Arcona was still at large as of Tuesday night.