The Portishead Railway is a branch line railway running from Portishead in North Somerset to the main line immediately west of Bristol, England. It was constructed by the Bristol & Portishead Pier and Railway Company, but it was always operated by its main line neighbour, and was more usually thought of as the Portishead branch or the Portishead railway.

Portishead is a town and civil parish in the North Somerset unitary authority area, in the county of Somerset, England. With a population of 26,366 at the 2021 Census, the town is located on the Severn Estuary opposite Cardiff and Newport in Wales. The town is 8 miles (13 km) to the west of Bristol and 18 miles northeast of Weston-super-Mare.