One firefighter suffered two broken vertebrae and was hospitalized at St. Francis Hospital in Poughkeepsie, the Times Herald-Record of Middleton reported Sunday.
The other four firefighters were treated and released from the hospital, and two have been cleared to return to duty.
"In my professional opinion, they would have been killed if they weren't wearing their seat belts," said Plattekill Fire Chief Chris Mancuso.
The accident took place Saturday night when the fire truck swerved to avoid hitting a vehicle traveling in the opposite direction that had veered into the wrong lane, the newspaper said.
The fire engine struck a guardrail, flipped onto its side, rolled over and came to rest on its roof.
The fire engine was en route to a traffic collision on the New York State Thruway at the time of the accident, the newspaper said.