A 1959 by-election was held for the British House of Commons constituency of Penistone in South Yorkshire on 11 June 1959. The seat had become vacant on the death of the Labour Member of Parliament Henry McGhee, who had held the seat since the 1935 general election.
The result was a hold for the Labour Party.
| Party | Candidate | Votes | % | ±% | |
|---|---|---|---|---|---|
| Labour | John Mendelson | 25,315 | 64.1 | +1.8 | |
| Conservative | John Bedford Deby | 14,196 | 35.9 | −1.8 | |
| Majority | 11,119 | 28.2 | +3.6 | ||
| Turnout | 39,511 | ||||
| Labour hold | Swing | +1.8 | |||