Earlier in her career, she won two bronze medals during the 2015–16 ISU Junior Grand Prix series in Austria and Latvia.

Making her senior Grand Prix debut, Choi placed 7th at the 2016 Skate Canada International and 8th at the 2016 NHK Trophy.

Called up to replace the injured Park So-youn at the 2017 Asian Winter Games in Sapporo, Japan, Choi won her country's first-ever figure skating gold medal at the event.

[10][11] South Korea also selected Choi to replace the injured Kim Na-hyun at the 2017 World Championships in Helsinki, Finland.

[11] She would place tenth in Finland, allowing her country to send two ladies' single skaters to the 2018 Winter Olympics in Pyeongchang and 2018 World Championships in Milan.

At the first of her two assignments on the 2017-18 Grand Prix circuit, the 2017 Cup of China, she placed a disappointing ninth, hampered by a foot injury.

[12] Choi and Kim Ha-nul were selected to compete at both the 2018 Winter Olympics in PyeongChang, South Korea, and the 2018 World Figure Skating Championships in Milan, Italy.

Choi reverted to her Doctor Zhivago free skate program for this and all subsequent competitions for the season, citing the difficulty in performing its replacement to the standard she desired.

[13] Choi received a standing ovation for her short program at the Olympics, including from South Korea's Yuna Kim.

[19] Returning to international competition, Choi began the 2019–20 figure skating season with a seventh-place finish at 2019 CS Nebelhorn Trophy.

Choi announced during a guest appearance on South Korean TV show, Sporty Sisters 2, that she would likely retire from competitive figure skating following the season, citing her struggles with boot problems and ankle injuries as the main reason behind the decision.

[20][24] Choi began the season in early October when she competed at the 2024 Korean Universiade and Asian Games Qualifiers.

She would finish fourth at the event and was ultimately selected to represent South Korea at the 2025 Winter World University Games.