Ritsuko Nasu (b.1963) received both Bachelor of Arts and Master of Music degrees in Percussion Performance from Kunitachi College of Music in Tokyo, Japan. She founded a marimba ensemble, Ensemble Mallet, in 1988 and has since served as the leader of the ensemble.

Ritusko also works as a freelance musician and has played with Anthony Plog (trumpet), Branimir Slokar (trombone), Gunma Symphony Orchestra, and Orchestre de chambre Jean-François Paillard. In addition, Ritsuko has played in a brass ensemble, The Brass, as a founding percussionist since 1989. This ensemble released two CDs from Victor Entertainment.

Besides a marimba/percussion performer, Ritsuko has actively served as a percussion instructor around Tokyo area. She is currently interested in and performs not only classical music but also traditional music of Japan and Brazil.