Barnsley South is a constituency of the House of Commons in the UK Parliament.

[2] Created as a result of the 2023 Periodic Review of Westminster constituencies, it was first contested at the 2024 general election.

It is represented by Stephanie Peacock of the Labour Party, who was MP for the predecessor seat of Barnsley East from 2017 to 2024.

The constituency is composed of the following wards of the Metropolitan Borough of Barnsley (as they existed on 1 December 2020): It comprises the bulk of Barnsley East (excluding the Cudworth and North East wards), with addition of the two Dearne wards from Wentworth and Dearne and the Kingstone ward from Barnsley Central.

[4] (All three predecessor constituencies were abolished under the 2023 review).