The crash happened shortly before 8 a.m. Sunday in the westbound lanes of Interstate 70 at Interstate 68 in Hancock.
Maryland state police say Sen. Fetterman was driving a Chevy Traverse when, for an unknown reason, he hit the back of a Chevy Impala.
Sen. Fetterman and his wife, Gisele, were taken to nearby War Memorial Hospital in West Virginia to be evaluated.
Sen. Fetterman was treated for a bruised shoulder and released, according to a statement from his office.
So far no citations have been issued. Maryland state police say the investigation is active and ongoing.
Fetterman's statement goes on to say he and Gisele are doing well and are happy to be back in their hometown of Braddock, Pennsylvania.