| Type: | Bishop |
| Honorific-Prefix: | His Grace |
| Sigismund Anton von Hohenwart | |
| Prince-Archbishop of Vienna | |
| Church: | Roman Catholic Church |
| Archdiocese: | Vienna |
| See: | St. Stephen's Cathedral |
| Term Start: | 20 June 1803 |
| Term End: | 29 June 1820 |
| Predecessor: | Christoph Anton Migazzi |
| Successor: | Leopold Maximilian von Firmian |
| Other Post: | Bishop of St. Pölten Bishop of Trieste |
| Birth Date: | 2 May 1730 |
| Birth Place: | Gerlachstein, Carniola, Austria, Holy Roman Empire |
| Death Place: | Vienna, Austrian Empire |
| Nationality: | Austrian |
Sigismund Anton Graf von Hohenwart, S.J. (2 May 1730 - 30 June 1820) was from 1791 to 1794 Bishop of Trieste, from 1794 to 1803 Bishop of St. Pölten, and from 1803 to 1820 he was Prince-Archbishop of Vienna.
Von Hohenwart was born in Gerlachstein, Carniola. He entered the Jesuit Order in 1746, studied theology in Graz, was a professor in Trieste and Ljubljana, and completed his studies in theology in 1758. In 1759 he was ordained a priest. From 1761 he taught at the Theresian Academy in Vienna and was from 1778 teacher of Emperor Francis II and his brothers in Florence. In 1791, he became the Bishop of Trieste and, in 1794, Bishop of St. Pölten. He received episcopal consecration from the Bishop of Ljubljana, Michel Leopold Brigido von Marenfels und Bresoviz, on 23 October 1791. From 1792 to 1803 he was also Apostolic Field Vicar.
On 29 April 1803, his former pupil, Francis II, appointed him Archbishop of Vienna, with confirmation taking place on 20 June.
He was a benevolent and learned church prince and conducted many visitations in his diocese. He endeavored to provide a good education for the students in the seminary. He promoted the admission of Redemptorists and Mechitarists in Vienna and supported Klemens Maria Hofbauer.
He was an opponent of Napoleon and signed reluctantly in 1809 a pastoral letter inviting Austrian priests to return to their parishes. On 11 March 1810, he took in the Augustinian Church before the church wedding of Marie Louise with Napoleon, who was represented by Archduke Charles.
He died in Vienna, where he is buried in the bishop's crypt of St. Stephen's Cathedral.