Yeonsun Joo, a former principal cellist of the Seoul Philharmonic Orchestra and the associate principal of the Kansas City Symphony, currently serves as principal of the Cellista Cello Ensemble. 

In 2008, she was selected as principal cellist for the Seoul Philharmonic, a position which had been vacant for more than three years since Myung-Whun Chung’s tenure as its music director. She has accumulated various experiences in chamber music performances with various masters, including a duo with Itzhak Perlman at Carnegie Hall, another duo with Lorin Maazel (as violinist). At the invitation of the Korean embassy in Australia, she also performed at the Sydney Opera House.

She has collaborated with many orchestras, including the Philadelphia Orchestra, KBS Symphony, Eastern Connecticut Symphony, and Seoul Philharmonic. She was awarded first place and grand prize in the cello section of the Busan MBC Competition, and was selected as prize winner for the senior section of the Philadelphia Orchestra Greenfield Competition. She has also received the first prize in the Connecticut Symphony Orchestra Competition and the grand prize in the Sorantin International Competition. She released a CD for all-Haydn works through SONY as a member of Quartet K (Knecht). Her second album, Death and Maiden, was published in 2015. In 2016, immediately after SONY issued her first solo album, which consisted of complete unaccompanied cello works by J.S. Bach, she performed her solo recital on the same program. In 2021, her second solo album 'Romantique' was released.

which included short cello pieces, was released. has been She has also appeared in a number of television programs, including KBS Yeonsun Joo currently serves as professor at Chung-ang University, as well as advisor for Hyundai Motor Chung Mong-Koo Scholarship Foundation.