Ronald Grigor Suny (born September 25, 1940) is an American historian and political scientist. Suny is the William H. Sewell Jr. Distinguished University Professor of History at the University of Michigan and served as director of the Eisenberg Institute for Historical Studies, 2009 to 2012 and was the Charles Tilly Collegiate Professor of Social and Political History at the University of Michigan from 2005 to 2015, and is Emeritus Professor of political science and history at the University of Chicago.

Suny was the first holder of the Alex Manoogian Chair in Modern Armenian History at the University of Michigan, after beginning his career as an assistant professor at Oberlin College. He served as chairman of the Society for Armenian Studies (SAS) in 1981 and 1984. He was elected president of the American Association for the Advancement of Slavic Studies (AAASS) in 2005 and given the Association for Slavic, East European, and Eurasian Studies (ASEEES) Distinguished Contributions to Slavic, East European, and Eurasian Studies Award in 2013. He has received the National Endowment for the Humanities Grant (1980–1981), the John Simon Guggenheim Memorial Fellowship (1983–1984), and a Research and Writing Grant, Program on Global Security and Sustainability, from the John D. and Catherine T. MacArthur Foundation (1998–1999), and was twice a fellow at the Center for Advanced Study in the Behavioral Sciences at Stanford (2001–2002, 2005–2006). He was a 2013 Berlin Prize Fellow at the American Academy in Berlin.