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Alexander Tah-ray Yui
俞大㵢
Official portrait, 2021
16th Taiwanese Representative to the United States
Incumbent
Assumed office 12 December 2023
President	Tsai Ing-wen Lai Ching-te
Preceded by	Hsiao Bi-khim
12th Taiwanese Representative to the European Union and Belgium
In office September 2023 – 12 December 2023
President	Tsai Ing-wen
Preceded by	Remus Chen
Succeeded by	Roy Lee
Vice Minister of Foreign Affairs
In office June 2021 – September 2023
Minister	Joseph Wu
Preceded by	Miguel Tsao
Succeeded by	Remus Chen
14th Taiwanese Ambassador to Paraguay
In office October 2015 – April 2018
President	Ma Ying-jeou Tsai Ing-wen
Preceded by	José María Liu
Succeeded by	Chou Lin
Personal details
Education	Texas A&M University (BA, MA) University of Pennsylvania London School of Economics
Occupation	Diplomat

Alexander Yui Tah-ray (Chinese: 俞大㵢; Wade–Giles: Yu² Ta⁴-lei²) is a Taiwanese diplomat currently serving as Taiwan's representative to the United States, succeeding Hsiao Bi-khim. A career diplomat, he previously served as the Taiwanese ambassador to Paraguay from 2015 to 2018, vice minister of foreign affairs from 2021 to 2023, and briefly the representative to the European Union and Belgium.

Yui was born to a family of diplomats.^[1] He attended high school in Panama.^[2] He then went to the United States and enrolled at Texas A&M University, where he earned a bachelor's degree in political science and foreign languages in 1986 and a master's degree in Spanish literature in 1988.^[3]

In 2002, Yui was a senior fellow at the Harvard Kennedy School. In 2010, he studied business at the Wharton School of the University of Pennsylvania and at the London School of Economics.^[3]

Yui served as the Representative of Taiwan to the European Union and Belgium in 2023.^[4] He was designated as the Taiwanese representative to the United States in November 2023 after the resignation of Hsiao Bi-khim.^[5] He had also served several diplomat offices including the vice minister of the Ministry of Foreign Affairs, Taiwanese ambassador to Paraguay, director of the Taiwanese Representative Office in the Latin America and the Caribbean.^[3]

In December 2023, Yui succeeded Hsiao Bi-khim as the Taiwanese representative to the United States.

Yui is fluent in Spanish and English, and conversational in French. He speaks English with a Panamanian accent. His father was also a diplomat.^[2]