St Stephen Walbrook is a church in the City of London, part of the Church of England's Diocese of London. The present domed building was erected to the designs of Sir Christopher Wren following the destruction of its medieval predecessor in the Great Fire of London in 1666. It is located in Walbrook, next to the Mansion House, and near to Bank and Monument Underground stations.

The Walbrook is a subterranean river in London. It gives its name to the Walbrook City ward and to a nearby street. It played an important role in the Roman settlement of Londinium.