Chien-yu Lee was born in Kaohsiung City, Taiwan. She began studying music in the music gifted class of Kaohsiung Municipal Kaohsiung Senior High School (KSHS), and she earned a Bachelor degree in Theory and Composition and Applied Music in National Sun Yat-sen University (NSYSU), and a Master degree in composition in National Taiwan Normal University (NTNU). She studied under Ching-Yu Hsiao, Szu-Hsien Lee and Ya-de Hsieh. During her undergraduate school years, she had completed the master's dissertation: An Analysis of Yuasa's Chamber Music A Winter Day: Homage to Basho and Self-Composition, and she had been awarded scholarships for several times. Recently, she is the composer in Residence at TMC Culture and Arts Foundation.

In 2024, Gim-Sii-Mien-San—for Chorus and Piano with TMC Taipei Youth Choir at National Concert Hall. In 2023, Cha-de-zi-wei—for Chorus and Piano with TMC Taipei Elegant Song Choir at National Performing Arts Center. The same year, she is the competition designated song arranger, Vocal Festival In Taoyuan. 2020-2022, the chamber music: Silent Confession and The Moon Forgets were selected for“Taipei International New Music Festival”, and works include pieces for choir：Sunlight(2023), Lang-Song-Shi-Hu(2023), bumper harvest(2022), Children of the Earth(2020)…etc.

Chien-yu has also received commissions by multiple ensembles, including Taipei Symphony Orchestra, Taipei Chinese Orchestra, TMC Culture and Arts Foundation, Pingtung Symphony Orchestra, Pingtung Symphony Band, Bean Theater, I-T Symphony Orchestra, Baroque Camerata, and Century Voice Choir. She devotes herself not only to music composition, but also to music teaching fields. She teaches as an adjunct instructor of several music gifted classes in Taipei, New Taipei, Taoyuan, and Kaohsiung. In 2018, she was invited to participate in the production of National Culture and Arts Foundation“The Composition of Taiwanese Composers.”