Mari-Leen Kaselaan (also known by stage name Mari-Leen) is an Estonian pop artist. She was born December 2, 1987 in Tartu, Estonia. She graduated from Elva Music School where she played violin and has studied at the Elva Song Studio and Ülenurme Music School under Ursel Oja.

Her musical career began as part of the group Ekvivalent, but her breakthrough came thanks to a competition run by the Estonian radio station Skyplus, in which Mari-Leen reached the final. However, she became known among the Estonian public as member of the girl band Suntribe. With Suntribe she represented Estonia at the Eurovision Song Contest 2005 with the song "Let's Get Loud".