Thomas C. Mann, American lawyer, politician, and diplomat, United States Ambassador to El Salvador (died 1999)

Thomas Clifton Mann was an American diplomat who specialized in Latin American affairs. He entered the U.S. Department of State in 1942 and quickly rose through the ranks to become an influential establishment figure. He worked to influence the internal affairs of numerous Latin American nations, typically focusing on economic and political influence rather than direct military intervention. After Lyndon B. Johnson became president in 1963, Mann received a double appointment and was recognized as the U.S. authority on Latin America. In March 1964, Mann outlined a policy of supporting regime change and promoting the economic interests of U.S. businesses. This policy, which moved away from the political centrism of Kennedy's Alliance for Progress, has been called the Mann Doctrine. Mann left the State Department in 1966 and became a spokesperson for the Automobile Manufacturer's Association.

The following is a list of United States ambassadors, or other chiefs of mission, to El Salvador. The title given by the United States State Department to this position is currently Ambassador Extraordinary and Minister Plenipotentiary.