Katrin Loo (born 2 January 1991) is a retired Estonian footballer who played as a forward for Naiste Meistriliiga club FC Flora and the Estonia women's national team.
Loo made her debut for the Estonian national team as soon as May 2007, in a friendly match against Latvia. In club competitions, she started her career playing for Flora Tallinn in Estonia's Meistriliiga before transferring in 2011 to Dayton Flyers in the NCAA. She subsequently moved to Finland's Naisten Liiga, playing first for NiceFutis and later for Merilappi United.