Marsel İlhan (Uzbek: Marsel Qahhorovich Hamdamov; born 11 June 1987) is a Turkish professional tennis player, ranked No. 1 in Turkey and with a career-high singles ranking of world No. 77 in March 2015. He is the first ever Turkish player to reach the 2nd round in a Grand Slam tournament, as well as the first Turkish player to win a Challenger Tournament and also the first Turkish player to enter the top 100 in the world ranking (first ranked 96th in September 2010).
Born in Uzbekistan, he emigrated to Turkey with his mother in 2004 and he started to play for the Taçspor Tennis Club of İstanbul. He was initially sponsored by Kia Motors Turkey. After several years of intensive training with his new coach Can Üner, a former Turkish tennis player, he made an unprecedented jump within one year from No. 1320 to No. 320 in 2007.
During 2007 and 2008 he won several Future Tournaments and in July 2008, he won his first ATP Challenger title at Ramat Hasharon Israel Open by defeating Ivo Klec from Slovakia by 2 sets 6–4, 6–4.