Police released a photo of the suspect, who is believed to be one of the six people responsible for the robbery in the Fordham section just before 10 p.m. Saturday.
The incident happened at the intersection of Southern Boulevard and East 175th Street.
The victim was not hurt, but his cell phone was stolen.
The suspect is described as a black male about 19 years old. He is 5-foot-9 and weighs 150 pounds.
Anyone with information in regards to this incident is asked to call Crime Stoppers at 1-800-577-TIPS (8477).