Seo Soojin (서수진; born March 9th, 1998), known mononymously as SOOJIN (Hangul: 수진; Katakana: スジン), is a South Korean singer under BRD Entertainment, previously under CUBE Entertainment. She debuted as a sub rapper, sub-vocalist and the main dancer of i-dle (아이들) on May 2, 2018. On August 14, 2021 she was removed from the group following an alleged bullying controversy.

Two years later, she made her debut as soloist with the EP AGASSY on November 8, 2023.

On April 18, 2025 it was confirmed that Soojin will be having her first comeback in May. On April 29, 2025 it was announced that Soojin will release her second mini album, RIZZ, on May 23, 2025.

On May 29, 2025, it was announced that SOOJIN will be making a comeback in August. On August 13, 2025 Soojin released a teaser for her first single album, "BADITUDE", set for release on August 27, 2025. Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.