HeeSun Yang was born in South Korea and began her viola studies at the age of ten. Following her studies at Seoul Arts High School and Yonsei University, she received her Masters degree at the Yale School of Music studying with Ettore Causa. She had her solo debut with the Janacek Sinfonietta in 2008 in Prague. She was the first prize winner in the Best Elgar Performance by Great Composers Competition and Music Journal Competition, and the Chongsin Music Competition. She was also a prize winner of the Gangnam-Weimar Competition and the Hyo Competition.

Heesun is a dedicated orchestral musician, she won the position of Assistant Principal Viola of Fort Worth Symphony in her first orchestral audition, and she has performed with the Houston Symphony and Saint Louis Symphony. She received a full scholarship to attend Gstaad Menuhin Festival in Switzerland in 2017 and she was a recipient of New Horizon Fellowship at the Aspen Music Festival and School two years in a row where she studied with James Dunham.

HeeSun is married to FWSO Principal Flutist Jake Fridkis.