Lee Joo-myung got her start in the entertainment industry as a model, first appearing in the music video for Yang Da-il’s song called Don’t Leave in 2016. In 2019, she debuted as an actress in the KBS2 drama My Fellow Citizens. In 2020, she made a cameo as Kim Joon-wan’s girlfriend PD Song in the tvN series Hospital Playlist. That same year, she played supporting roles in OCN’s Missing: The Other Side and MBC’s Kairos. Her work in the latter scored her a Best New Actress nomination at the MBC Drama Awards. In 2021, she joined the cast of the four-episode MBC series Check Out the Event. In 2022, she portrayed one of the main characters in the hit tvN drama Twenty Five Twenty One.