| Election Name: | 2001 Tipperary South by-election |
| Country: | Ireland |
| Type: | presidential |
| Ongoing: | no |
| Previous Year: | 2000 Tipperary South |
| Election Date: | 30 June 2001 |
| Next Year: | 2002 general election |
| Turnout: | 31,907 (58.5%) |
| 2Blank: | Percentage |
| 3Blank: | Final count |
| Nominee1: | Tom Hayes |
| Party1: | Fine Gael |
| 1Data1: | 11,446 |
| 2Data1: | 35.9 |
| 3Data1: | 15,791 |
| Nominee2: | Phil Prendergast |
| Party2: | Independent politician |
| 1Data2: | 7,897 |
| 2Data2: | 24.8 |
| 3Data2: | 12,891 |
| Nominee3: | Michael Maguire |
| Party3: | Fianna Fáil |
| 1Data3: | 8,461 |
| 2Data3: | 26.5 |
| 3Data3: | – |
| Nominee4: | Denis Landy |
| Party4: | Labour Party (Ireland) |
| 1Data4: | 4,103 |
| 2Data4: | 12.9 |
| 3Data4: | – |
| Map Size: | 200px |
| TD | |
| Before Election: | Theresa Ahearn |
| Before Party: | Fine Gael |
| After Election: | Tom Hayes |
| After Party: | Fine Gael |
A by-election was held in the Dáil Éireann Tipperary South constituency in Ireland on 30 June 2001. It followed the death of Fine Gael Teachta Dála (TD) Theresa Ahearn on 20 September 2000.
The election was won by Fine Gael Senator Tom Hayes. The other candidates being Phil Prendergast standing as an Independent, Michael Maguire for Fianna Fáil and Denis Landy for the Labour Party. Prendergast, Maguire and Landy were all members of South Tipperary County Council at the time.
This was the second by-election in Tipperary South during the 28th Dáil.