Antonio Castro Leal (March 2, 1896 – January 7, 1981) was a Mexican diplomat and intellectual.

Antonio Castro Leal was born on March 2, 1896, in San Luis Potosí.

He received his licenciate and doctor of law degrees from the National Autonomous University of Mexico and his PhD from Georgetown University in Washington, D.C. Castro Leal was rector of UNAM in 1929 during the student strikes that ultimately lead to the university becoming autonomous, after which he resigned his post.

He lived in Paris from 1949 to 1954 as Mexico's ambassador and executive board member for UNESCO, after which he moved to Coyoacán, in Mexico City, where he lived for the rest of his life.

Castro Leal also translated Maurice Dobb's Introduction to Economics for Mexico's Fondo de Cultura Económica.