| Jurisdiction: | Diocese |
| Tainan | |
| Latin: | Dioecesis Tainanensis |
| Local: | 天主教台南教區 |
| Territory: | Tainan and Penghu |
| Province: | Taipei |
| Area Km2: | 2,870 |
| Population: | 1,997,000 |
| Population As Of: | 2015 |
| Catholics: | 8,274 |
| Catholics Percent: | 0.4 |
| Parishes: | 44 |
| Denomination: | Roman Catholic |
| Established: | 21 March 1961 |
| Priests: | 22 |
| Bishop: | John Baptist Huang Min-cheng |
| Metro Archbishop: | Thomas Chung An-zu |
| Suffragan: | for one --> |
| Archdeacon: | for one--> |
| Emeritus Bishops: | Bosco Lin Chi-nan John Lee Juo-wang |
| Map: | Taiwan - Diocesi di Tainan.png |
| Website: | Website of the Diocese |
The Diocese of Tainan (Latin: Dioecesis Tainanensis) is a Latin Church diocese of the Catholic Church in Taiwan.
Erected in March 1961 from territories belonging to the former Apostolic Prefecture of Kiayi, the diocese is a suffragan of the Archdiocese of Taipei.