A BART spokeswoman says the shooting took place in a bus zone outside the Bayfair BART station around 12:21 p.m. Saturday.
Spokeswoman Alicia Trost says the woman wounded in the shooting is being treated for non-life threatening injuries. The dead man's name was not immediately released.
One suspect has been detained and police are looking for three more suspects.
The station was closed for more than five hours while police investigate.