It happened around 6 p.m. on the 1700 block of Atlantic Avenue.
According to the Atlantic County Prosecutor's Office, all four men were rushed to Atlanticare Regional Medical Center City Campus after the shooting. One of the men was later pronounced dead.
There is no immediate word on the conditions of the three other victims.
Police are still investigating what sparked the gunfire.
Anyone with any information is asked to call the Atlantic City Police Department or the Atlantic County Prosecutor's Office at 609-909-7800.