An election to the 58th Parliament of the United Kingdom for the constituency area of Cardiff South and Penarth, held as part of the general election on 12 December 2019.
Labour hold by Stephen Doughty with a majority of 12,737 - 25.2% - on a turnout of 64.2%.
Candidates
| Name | Party | Vote | Vote share | Vote change |
| DOUGHTY, Stephen | Lab / Co-op | 27,382 | 54.1% | -5.4% |
| BROOM, Philippa | Con | 14,645 | 29.0% | -1.2% |
| SCHMEISING, Dan | LD | 2,985 | 5.9% | 3.1% |
| ADAM, Nasir | PC | 2,386 | 4.7% | 0.5% |
| PRICE, Tim | BRX | 1,999 | 4.0% | - |
| BARKER, Ken | Green | 1,182 | 2.3% | 1.3% |
Under section 13(b) of the Representation of the People Act 1985, a candidate gaining 5% or less of the vote share will forfeit their deposit.
An electorate of 78,837, having a valid vote count of 50,579 and an invalid vote count of 160.
Result declared at 03:41 on 13 December 2019.