UDTT (우당탕탕 소녀단) is a 5-member South Korean girl group under SW Entertainment. The group consists of Risako, Han Chaehee, Koo Hanna, Jessica, and Kwon Yejin. Jung Sena left the group on March 26, 2025. They released their first pre-debut single titled “𝐑𝐄𝐓𝐑𝐘” on December 11, 2024. They officially debuted on April 29, 2025, with their first single album, School Rush.
