Tsung-Dao Lee ( Pinyin: Lǐ Zhèngdào) (born November 24, 1926) is a Chinese American physicist who did work on high energy particle physics, symmetry principles, and statistical mechanics. In 1957, at age 31, Lee received the Nobel Prize for his work on the violation of parity law, with Chen Ning Yang, experimentally verified by Chien-Shiung Wu. Lee and Yang were the first Chinese Nobel winners.

Lee's hometown is Suzhou, Jiangsu. He was born in Shanghai, China, and received his middle school education in Shanghai and Jiangxi. The first part of his university education began at Zhejiang University, but was interrupted by the war, so he continued at the National Southwest Associated University in Kunming the next year. Lee went to the University of Chicago in 1946 and completed his PhD with Enrico Fermi. In 1953, he became an assistant professor at Columbia University. Three years later, at age 29, Lee became the university's youngest full professor. He remains an active member of the Columbia faculty and has held its highest academic rank, University Professor, since 1984.

Soon after the establishment of relations with the PRC, Lee and his wife, Hui-Chun Jeannette Chin ( Qín Huìjùn), were able to go to China, where Lee gave a series of lectures and seminars, and organized the China-U.S. Physics Examination and Application (CUSPEA).

In 1999, Lee established the Chun-Tsung Endowment Fund in Beijing in memory of his wife, Hui-Chun Chin, who passed away 3 years earlier. The Chun-Tsung scholarships are awarded to undergraduates, usually in their 2nd or 3rd year, at five universities in China. Students selected for such scholarships are named "Chun-Tsung Scholars" . Chin and Lee were married in 1950 and have two sons: James and Stephen.

Lee reads whodunit novels when he does not work on physics.

His English given name differs dramatically from the then-existing Chinese Romanizations, such as Wade-Giles and Gwoyeu Romatzyh.