Momčilo Krajišnik (Serbian Cyrillic: Момчило Крајишник; born 20 January 1945) is a former Bosnian Serb political leader, who along with Radovan Karadžić co-founded the Bosnian Serb nationalist Serb Democratic Party (SDS). Between 1990-92, he was Speaker of the People's Assembly of Republika Srpska. Between June and December 1992, he also served as member of the expanded Presidency of Republika Srpska.
After the Bosnian War, he was elected Serb member of the tripartite Presidency of Bosnia and Herzegovina in the September 1996 and served in that post from October 1996 to October 1998. He lost his bid for re-election in 1998 to Živko Radišić. In 2006, Krajišnik was found guilty of committing crimes against humanity during the Bosnian War (1992–95) by the International Criminal Tribunal for the former Yugoslavia (ICTY) and was sentenced to 20 years' imprisonment. He was later granted early release on 1 September 2013, and he returned to Republika Srpska.
An ethnic Serb, Krajišnik was born in Zabrđe, a village near Sarajevo in central Bosnia and Herzegovina.
On 15 October 1991, the parliament of SR Bosnia and Herzegovina passed a resolution on the sovereignty of Bosnia and Herzegovina, in spite of strong opposition from Bosnian Serb deputies. Ten days later, the Serb Democratic Party (SDS) formed a Bosnian Serb Assembly, with Momčilo Krajišnik acting as its president. The Bosnian Serb Assembly began establishing parallel government structures.