The aircraft, a Piper PA-28, set down at around 3:20 p.m. on the northbound side of the Major Deegan Expressway in the Bronx, in an area where the highway passes through Van Cortlandt Park.
The Federal Aviation Administration said three people were on board. Police and fire officials said neither the male pilot nor two female passengers appeared to have been badly hurt. All were taken to a Bronx hospital for non-life-threatening injuries, said Mayor Bill de Blasio.
De Blasio told reporters the plane had departed from Danbury Municipal Airport and was making the return trip when it experienced engine problems.
"We have...extraordinary situation and actually a bit of a miracle, thank God, that happened today in our city," he said, calling the successful highway landing, without any serious injuries or deaths, "amazing."
"I thought I'd seen everything in my life," he said.
The FAA said damage to the aircraft was minor. Photos taken by bystanders showed blue and white plane largely intact, but resting on its belly by the snowy edge of the road. The plane's landing gear appeared in the photos to have collapsed.
A maintenance crew of city Department of Transportation workers fixing potholes on the northbound side of the highway noticed the plane in distress heading toward them and stopped traffic, clearing space for the plane to land, a DOT spokesman said.
The DOT crew then helped the plane's occupants out of the aircraft and inside a heated truck until emergency workers arrived, the spokesman said.
It wasn't immediately clear what kind of engine problems the plane experienced. A spokeswoman for the FAA said it was investigating but said the National Transportation Safety Board would take over the investigation if it was determined the aircraft sustained a significant amount of damage.
There were no fires or gas leaks and emergency workers removed the plane's fuel to secure the scene, de Blasio said.
The highway was closed and emergency personnel were on the scene until about 6 p.m., when the plane was taken away on a flatbed truck to a local aviation facility, the FAA said.
FAA records indicated the plane was registered to an owner in South Salem.
Patricia Sapol, 29, of West Point, was driving south on the highway with her husband when they saw emergency vehicles surrounding the downed plane near exit 13, about 15 minutes after the landing.
"We couldn't believe it! We thought, 'Oh my god that's a plane!' It was pretty incredible," she said. "The fact that there was no actual crash we thought was pretty surprising."