Police say passengers were lining up to get on a charter bus around 9 a.m. PT Saturday morning in the area of 63rd Avenue and Ross Street.
The woman was trying to board, but fell outside when the bus began to roll backwards.
Witnesses tell CBC News the bus rolled back about a block to Marine Drive before it was finally stopped.
Paramedics initially thought she only had minor injuries, but the woman died en route to hospital. Three other people also suffered minor injuries.
Vancouver Police are on the scene interviewing witnesses today.
The driver of the charter bus is co-operating with investigators. The woman's name is not being released.