Kye Beom-ju (, born November 8, 1991), better known by the stage name Bumzu (), is a South Korean record producer, songwriter and singer. He signed to Pledis Entertainment early in his career, and has been co-CEO of the Prismfilter Music Group since 2016.
He is best known for his work with Pledis Entertainment labelmates NU'EST and Seventeen, and has amassed credits working with other South Korean artists including Shinee, Fromis 9, NCT 127, TWS, and BTS's Jin. Since 2019, he has been a full member of the Korea Music Copyright Association (KOMCA), a status given to music creators who meet the highest levels of professional standards and copyright royalties. In 2025, he also became a member of The Recording Academy.
Bumzu was born in Seoul, South Korea, on November 8, 1991. He learned the violin as a child, and by the age of high school, he became active in Hongdae's underground music scene. His first mainstream work was composing for H.O.T's Jang Woo-hyuk's "Don't Go, Go Away" in 2011. He then participated in the singing competition show Superstar K 4 at the age of 22, which has been noted as his big break. Following the show, he began producing songs for Pledis artists including After School and NU'EST, and has produced songs alongside Woozi for Seventeen since their debut song "Adore U". He also worked on vocal coaching the members of Seventeen early in their careers.
Since 2016, he has been the co-CEO of the music production company Prismfilter Music Group. In 2024, Bumzu started producing music for Pledis' new group TWS under the pseudonym "Wasurenai". In February, he was awarded KOMCA's grand prize, having been the highest-earning songwriter for K-pop in 2023. On December 7, 2025, he won the Legendary Producer award at the 10th Asia Artist Awards, his second consecutive year winning a producer award at the ceremony. The same year, he became a member of The Recording Academy.