Thomas Yeh Sheng-nan (Chinese: 葉勝男; pinyin: Yè Shèngnán; born 26 June 1941) is a Taiwanese prelate of the Roman Catholic Church and diplomat of the Holy See.

[1][2] Thomas Yeh Sheng-nan was born on 26 June 1941, in Kaohsiung, Taiwan, and was ordained priest on 27 March 1971, for the Diocese of Tainan.

[3] Yeh entered the diplomatic service of the Holy See on 8 March 1976, and served in the Pontifical diplomatic missions in Nicaragua, Sri Lanka, Zambia, Algeria, Iraq, Australia, Senegal and Great Britain.

On 10 November 1998, he was elected Titular Archbishop of Leptis Magna, and at the same time named Apostolic Nuncio to Sri Lanka.

[4] His episcopal consecration took place on 20 December 1998; Cardinal Edward Idris Cassidy was the principal consecrator, with archbishops Stanislaus Lo Kuang and Carlo Maria Viganò, as principal co-consecrators.