Evgenij Petkov Ermenkov (Bulgarian: Евгени Петков Ерменков; born September 29, 1949 in Sofia) is a Bulgarian chess Grandmaster (GM). He played for Palestine from October 2003 to December 2010.
Ermenkov won the Bulgarian Championship in 1973, 1975 (after a play-off), 1976, 1979 (after a play-off) and 1984 (jointly).
In international competition, he has had many tournament victories, including Albena 1977 (and 1979), Plovdiv 1978 (and 1979), Varna 1986, Dieren 1990 (Open Dutch Championship), Beirut 2004 and Imperia 2005.
He has a long and illustrious career in team chess, beginning at the World Student Olympiad of 1972, where he represented his country of birth. Graduating to the full Bulgarian men's team, he first played at the European Team Chess Championship in 1977 (Moscow) and won an individual bronze medal in 1983 (Plovdiv). At the Olympiad, he represented Bulgaria from 1978 to 1992, taking individual bronze in 1990.
From 1992, there was a break from team chess which lasted twelve years, during which time he switched his place of residence and chess registration to Palestine. Playing for his adopted nation in Olympiads from 2004 to 2008, he won the gold medal at Calvià 2004 for the best result on first board (87.5%, 10½/12) and at Turin 2006, the silver medal (85%, 8½/10, again on top board).
Ermenkov earned the International Master (IM) title in 1974 and the GM title in 1977.