The Gospel Oak to Barking line (sometimes unofficially called the Goblin) is a railway line in London. It is 13 miles 58 chains (22.1 km) in length and carries both through goods trains and London Overground passenger trains, connecting Gospel Oak in north London and Barking Riverside in east London. The line is part of Network Rail Strategic Route 6, and is classified as a London and South East Commuter line.

For much of its existence the line has played a minor role in London's transport system; however in recent years it has received significant investment to increase its capacity, including full 25kV AC overhead electrification, completed in 2018. At the eastern end of the line, the extension to the Barking Riverside regeneration site opened on 18 July 2022.