The woman was taken to Queen Elizabeth Hospital after emergency services were called to the scene on Blaydon Road, Wolverhampton following an incident involving a bus and a pedestrian around 4.45pm on Monday.
An air ambulance, one ambulance and a paramedic officer were called to the incident, where the woman was given advanced trauma care before being taken to hospital for further treatment.
A spokeswoman from West Midlands Ambulance Service said: "On arrival crews discovered an elderly woman who was the pedestrian.
“She was assessed at the scene and had sustained serious injuries.
“She received advanced trauma care from ambulance staff at the scene and treatment continued en route to Queen Elizabeth Hospital.
“Nobody from the bus required treatment."