The crash happened at about 5 p.m. in the 1700 block of Geneva Avenue near the city's southern border, a few blocks from the Cow Palace.
Police spokesman Lt. Troy Dangerfield said the woman, identified by the medical examiner's office as Maria Francisco, was not in a crosswalk when an eastbound black van struck her.
She was pronounced dead at the scene.
Dangerfield said the 23-year-old woman who was driving the van stopped afterward and cooperated with police, telling them she had hit the brakes before the collision.
"It's still under investigation, but it appears to be a tragic accident," Dangerfield said.
The woman was not charged in connection with the collision, but was cited for driving on a suspended license, Dangerfield said.