Leonard Petrosyan (; 13 October 1953 – 27 October 1999) is an Armenian politician who was the acting President of the Nagorno-Karabakh Republic from 20 March 1997 to 8 September 1997. He also served as Prime Minister of the Nagorno-Karabakh Republic from December 1994 to June 1998. He was killed in the 1999 Armenian parliament shooting while serving as Deputy Prime Minister of Armenia.