Oto Luthar (born 11 August 1959) is a Slovenian historian.
He was born in Murska Sobota, Slovenia, then part of the Socialist Federal Republic of Yugoslavia.
He studied history at the University of Ljubljana, graduating under the supervision of Peter Vodopivec and Bogo Grafenauer in 1986.
He is a coordinator of the Module of Culture History at ZRC SAZU Graduate School.
In 2011, Luthar was awarded the Austrian Cross of Honour for Science and Art.