Off-duty medics and police officers tried to provide aid at the scene, but he was declared dead shortly after.
Per the report, San Francisco police spokesman Gordon Shyy says there were a number of people in close proximity who saw the man fall from the elevated Jamestown walkway that travels around Candlestick Park.
The man, whose name is not being released until the medical examiner's office can notify the family, was identified by witnesses to be intoxicated at the time of the fall.
Fan safety is an important topic in professional sports.
Shortly after a rain delay halted play between the Atlanta Braves and the Philadelphia Phillies, a fan fell to his death at Turner Field in August. In 2011, a baseball fan died at the Ballpark in Arlington trying to catch a ball tossed into the stands by former Texas Rangers outfielder Josh Hamilton.
Shortly after the latter incident, the Rangers announced initiatives to make their stadium safer.