The incident involved a car and motorcycle on Chiswick High Road just after 7am.
Paramedics from the London Ambulance Service (LAS) treated a man, aged in his 40s, for hip injuries before he was taken to St Mary's Hospital.
A LAS spokesperson said: "We were called at 7.14am to Chiswick High Road to an accident involving a motorcycle.
"We sent an ambulance crew and a responder in a car.
"We treated a man in his 40s for hip injuries and he was taken as a priority to St Mary's Hospital."
The road was closed for over an hour and motorists experienced heavy delays in the area.
A police spokeswoman said: "We were called at 7.10am this morning to a car and motorcycle collision.
"A motorcyclist in his 40s was taken to a central London hospital with serious injuries."