Montville Officer Louis Violante was on routine patrol when the accident occurred around 1 a.m. Sunday.
He was hospitalized in stable condition and was due to have surgery later Sunday, but his injury was not considered life-threatening.
The cause of the accident was not immediately clear, and the crash remained under investigation late Sunday morning.
Emergency crews responded to the scene after the 33-year-old reported the crash, using the police radio in his cruiser.
He was the only person in the vehicle at the time. Violante has served on the Montville force since 2004.
Get Eyewitness News Delivered