Lee Se-hee made her entertainment industry debut in 2015 with an appearance in the music video for Na Yoon-kwon’s song 364 Days of Dream. She was then cast in small roles in the films Midnight Runners and Fengshui in 2017 and 2018, respectively. In 2019, she became part of the tvN cop comedy Catch the Ghost. In 2020, she played a supporting role in the JTBC coming-of-age drama Live On. In 2021, she joined the second season of the popular tvN series Hospital Playlist. That same year, she starred in the high-rating KBS2 weekend drama Young Lady and Gentleman. Her work in the series won her Best New Actress and Best Couple with Ji Hyun-woo at the KBS Drama Awards.

Lee Se-hee graduated from Cheonan Girls’ High School. She was a licensed dental hygienist prior to pursuing an acting career.