Katriin Saar (born 11 March 2002) is an Estonian tennis player.
She won the Under-16 girls' singles title at the 2017 Orange Bowl.
Saar made her Fed Cup debut for Estonia in 2018.
Saar has a career-high ITF juniors ranking of 186,which she achieved on 21 May 2018.
Saar made her Fed Cup debut for Estonia in 2018, while the team was competing in the Europe/Africa Zone Group I, when she was 15 years and 334 days old.