Thiruvenkatachari Parthasarathy (29 February 1940 - 22 September 2023), known and published as T. Parthasarathy, was a game theorist and distinguished Indian mathematician and the co-author of a book on game theory with T. E. S. Raghavan, and of two research monographs, one on optimization and one on univalence theory, published by Springer-Verlag. He was a former president of the Indian Mathematical Society.

He received his B.Sc and M.Sc degrees from University of Madras. He worked on the topic of "Minimax Theorems and Product solutions for simple games" under the guidance of C. R. Rao and received his PhD in 1967 from the Indian Statistical Institute, Kolkata. He delivered many lectures and seminars at University of Madras, Indian Statistical Institute, and Chennai Mathematical Institute.

Parthasarathy received Shanti Swaroop Bhatnagar Award for Mathematical Sciences (1986). He was elected as Fellow of the Indian Academy of Sciences (1988) and Indian National Science Academy (1995).

He died on September 22, 2023, at the age of 83 at his Chennai residence.