The suspect walked into an Astoria Bank branch at 97-33 Queens Blvd. shortly after 4:30 p.m. on Dec. 21, officials said.
He passed a demand note to a bank employee, who handed him the money, according to the NYPD.
The robber fled in an unknown direction, police said.
Authorities described the man as standing approximately 5-foot-10 and weighing about 200 pounds. He was last seen wearing a black and white leopard print waist-length jacket and a dark-colored hooded sweatshirt.
Anyone with information is asked to call Crime Stoppers at 1-800-577-TIPS (8477).