Mario Ramón Beteta Monsalve (7 July 1925 - 5 October 2004) was a Mexican economist who served as the last Secretary of Finance in the cabinet of President Luis Echeverría (1975–76), as director-general of Pemex (1982–87) and as governor of the State of México (1987–89).

Beteta was born in Mexico City into a family led by General Ignacio Beteta, a well-known artist and former chief of staff of President Lázaro Cárdenas and brother of Ramón Beteta, who also served as Secretary of Finance during the presidency of Miguel Alemán Valdés. He graduated from the National Autonomous University of Mexico (UNAM) with a bachelor's degree in Law (1948), completed a master's degree in Economics at the University of Wisconsin (1950) and married Gloria Leal Kuri before working as a professor of Introductory Economics and Monetary Theory at the National School of Economics (UNAM, 1951–59).

He worked as director-general of Credit (1964–70) and then as Undersecretary of the Treasury (1970–75) at the Secretariat of Finance, and when the secretary, José López Portillo, resigned to run for president as candidate of the Institutional Revolutionary Party (PRI), Beteta was appointed as substitute. During his tenure, he had to deal with the 1976 peso devaluation.