The victim, who was said to be in his late 30s, was found around 10:40 p.m. Monday at San Julian and Sixth streets.
Police say it appears the man was confronted by the suspects and was either pushed or punched.
He hit his head on the concrete and was pronounced dead at the scene.
"We think it was a robbery that went bad," LAPD Sgt. Richard Tamez said.
Anyone with information was asked to call the LAPD Central Station at (213) 485-3294.
CNS contributed to this report.