NEW YORK — Republican mayoral candidate Curtis Sliwa was undergoing medical treatment Friday afternoon after a yellow cab slammed into him in Midtown Manhattan, a campaign adviser said.

Sliwa got hit by the taxi near the corner of 50th Street and Sixth Avenue after getting out of his campaign van to walk over to the nearby WABC radio studio for an interview, the adviser, Rob Cole, said.

“He jumped out of the van, and the cab didn’t see him and accidentally hit him. He went 6 feet in the air and hit the ground,” Cole told the New York Daily News.

The cabbie didn’t stop after the accident, Cole said. “But Curtis said it was his fault,” he added.

Though he has since canceled all campaign events for Friday, Cole said Sliwa went ahead with his radio interview after the crash.

“As it was over, he realized he was in severe pain in his right arm in particular,” Cole said.

Sliwa subsequently headed to Lenox Hill Hospital on the Upper East Side for a checkup, according to Cole.

“I don’t know how he got through the show. I really don’t,” Cole said. “He has scratches, bruises and some bleeding on his right arm and left arm.”

The NYPD did not immediately have any information about the accident.

Sliwa, the red beret-wearing founder of the crime-fighting Guardian Angels group, is considered a long shot in Tuesday’s election against Democratic mayoral candidate Eric Adams.

Adams, who has blasted Sliwa as a “clown” on the campaign trail, offered support for his GOP opponent after getting word of the Midtown crash.

“I’d like to wish him a speedy recovery, and I hope to see him back out on the trail this weekend,” Adams tweeted.

Cole said a taxi cab is no match for Sliwa, who has suffered several life-threatening injuries over the course of his tenure as the eccentric leader of the Guardian Angels.

“He was shot five times,” he said, “so a cab isn’t going to stop him.”