King William Street is the name of a street in the City of London. It runs from a junction at the Bank of England, meeting Poultry, Lombard Street and Threadneedle Street, south-east, where it meets a junction with Gracechurch and Cannon Street. It continues south after this junction, and becomes London Bridge.

The nearest tube stations are Bank and Monument. The disused King William Street tube station was sited on this road.