Nils Petter Gleditsch (born 17 July 1942 in Sutton, Surrey, Great Britain) is a Norwegian sociologist and political scientist. He is Research Professor at the Peace Research Institute Oslo (PRIO). In 2009, Nils Petter Gleditsch was awarded the annual Award for Outstanding Research by the Research Council of Norway.
In 1982 he was convicted in Norway of a violation of the national security paragraphs of the penal code, in the Wilkes/Gleditsch trial. His prison sentence was suspended.
Nils Petter Gleditsch is the son of Kristian Gleditsch and Nini Haslund Gleditsch, and the nephew of Ellen Gleditsch.
Following studies in philosophy and economy Gleditsch became mag.art. (PhD equivalent) in sociology at the University of Oslo. In 1966-67 he read sociology, social psychology and international relations at the University of Michigan in United States.
Since 1964, Gleditsch has been at the Peace Research Institute Oslo (PRIO), first as a student, later as researcher and research leader. He was Director of PRIO in 1972 and 1977-78. From 2002-2008 he led the working group 'Environmental Factors of Civil War' at PRIO's Centre for the Study of Civil War, apponted Centre of Excellence by the Research Council of Norway. Since 1993 he has also been Professor at NTNU. Gleditsch was editor of Journal of Peace Research 1983-2010, succeeded by Henrik Urdal. Gleditsch served as President for the International Studies Association (ISA) 2008-09.
He is a member of the Norwegian Academy of Science and Letters.