National Express West Midlands warned passengers to expect disruption after the tree came in Birmingham Road, Shenstone.
It hit the service between Hill Hook and Lichfield, with service X3 terminating at Hill Hook.
NX West Midlands tweeted: "Fallen tree blocking Birmingham Road, #Shenstone.
"Service X3 is terminating at Hill Hook."
"There is currently no service between Hill Hook and Lichfield," the tweet continued.
"Apologies for any inconvenience caused".