Police are looking for a man who sucker-punched a city sanitation worker in the Bronx last week.

The attack on the supervisor with the city sanitation department occurred last Thursday on Grant Highway near 169th Street about 2:20 p.m., cops said.

Surveillance footage from the assault shows the suspect sock the man with his right hand, then dart across the street.

The sanitation worker, who stayed upright, turned around and raised his arms in disgust, watching the suspect run away, the video shows.

The victim refused medical attention, police said.

The suspect was last seen wearing gray sweatpants, a black jacket and a red baseball hat.