Hammersmith South was a borough constituency in the Metropolitan Borough of Hammersmith in west London. It returned one Member of Parliament (MP) to the House of Commons of the Parliament of the United Kingdom, elected by the first-past-the-post system.

Hammersmith was a civil parish and metropolitan borough in London, England. It was formed as a civil parish in 1834 from the chapelry of Hammersmith that had existed in the ancient parish of Fulham, Middlesex since 1631. The parish was grouped with Fulham as the Fulham District from 1855 until 1886, when separate parish administration was restored. In 1889 it became part of the County of London and in 1900 it became a metropolitan borough. It included Hammersmith, Wormwood Scrubs, Old Oak Common and Shepherd's Bush. In 1965 it was abolished and became the northern part of the London Borough of Hammersmith, since 1979 renamed the London Borough of Hammersmith and Fulham.