The motorbike and car crashed on Sedgley Road East near Tipton at around 3.15pm on Sunday.
The motorcyclist left the scene while the passenger, a man in his 20s, suffered a serious foot injury and was taken to Russells Hall Hospital in Dudley.
One ambulance attended the scene.
A woman and three children in the car were assessed by ambulance staff but did not require hospital treatment.
Police closed the road while the scene was made safe.