The accident happened at around 6:30 p.m. at the Edgewood Avenue intersection.
The officer that was struck was assisting another cop in a routine traffic stop.
When he got out of his vehicle to walk to the other officer, he was hit by the car.
The driver of that car stayed at the scene.
The police officer was taken to Jacobi Medical Center in serious condition.
Boston Post Road is closed at Edgewood Avenue for the accident investigation.