The victim was in a dance cafe in the 200 block of Terry A. Francois Boulevard near Third Street when he got into an argument with another man at about 1:40 a.m., San Francisco police Officer Samson Chan said.
The argument continued outside and eventually turned violent, according to Chan.
"That's when the suspect pulled out a gun and shot the victim in the chest," Chan said.
The victim was transported to San Francisco General Hospital where he died later this morning from the one gunshot wound, according to Chan.
The suspect fled the scene and had not been arrested as of 3 p.m.
Police are encouraging anyone who may have witnessed the shooting to contact the Police Department's anonymous tip line at (415) 575-4444.