ロバート・マクマホン(Robert J. McMahon, 1949年-)は、アメリカ合衆国の歴史学者。専門は、冷戦史、とくにアメリカの東南アジア・南アジア政策。

フロリダ大学教授を経て、現在、オハイオ州立大学歴史学部教授。

著書 単著 Colonialism and Cold War: The United States and the Struggle for Indonesian Independence, 1945-49, (Cornell University Press, 1981). The Cold War on the Periphery: the United States, India, and Pakistan, (Columbia University Press, 1994). The Limits of Empire: the United States and Southeast Asia since World War II, (Columbia University Press, 1999). The Cold War: A Very Short Introduction, (Oxford University Press, 2003). Dean Acheson and the Creation of an American World Order, (Potomac Books, 2008).

編著 Major Problems in the History of the Vietnam War: Documents and Essay, (D.C. Heath, 1990).

共編著 The Origins of the Cold War, co-edited with Thomas G. Paterson, (Heath, 1991).

編纂史料 Foreign Relations of the United States, 1955-1957, vol. 4: Western European Security and Integration, co-edited with Nancy E. Johonson and Sherrill B. Wells, (United States Government Printing Office, 1986). Foreign Relations of the United States, 1955-1957, vol. 8: South Asia, co-edited with Stanley Shaloff, (United States Government Printing Office, 1987). Foreign Relations of the United States, 1955-1957, vol. 10: Foreign Aid and Economic Defense Policy, co-edited with William F. Sanford and Sherrill B. Wells, (United States Government Printing Office, 1989). Foreign Relations of the United States, 1955-1957, vol. 22: Southeast Asia, co-edited with Harriet D. Schwar and Louis J. Smith, (United States Government Printing Office, 1989). Foreign Relations of the United States, 1958-1960, vol. 17: Indonesia, (United States Government Printing Office, 1994).