Lee Hae-in (figure skater)

In January 2018 at the 2018 senior South Korean Championships, Lee was 9th.

In the 2018–2019 season, she debuted in the ISU Junior Grand Prix series.

In January 2019 at the 2019 senior South Korean Championships, she won the bronze medal (behind You Young and Lim Eun-soo).

In March 2019, Lee (along with You Young) represented South Korea at the 2019 World Junior Championships in Zagreb, Croatia. She ranked 14th in the short, which put her in only the third-to-last warm-up group for the free skate. In the free, she placed 7th, raising to 8th overall. (You Young was 11th in the short and 5th in the free skate and finished 6th.)

In July 2019, Lee Hae-in participated in the ISU Junior Grand Prix Korean qualification competition held in Taeneung, South Korea, where she came in first in the short program, free program, and overall. Following the competition, she was selected and assigned to two ISU Junior Grand Prix events, JGP Latvia and JGP Croatia.

At JGP Latvia, she became the third Korean woman ever to become an ISU Junior Grand Prix champion, following Yuna Kim and Kim Hae-jin. She finished third in the short program behind Maiia Khromykh and Daria Usacheva of Russia and the placed first in the free program to win the event with a combined total of 197.63 points, more than three points ahead of silver medalist Usacheva. She set personal best scores in the short program, free program, and overall. This event marked the first Junior Grand Prix event won by a Korean lady since Kim Hae-jin's victory at JGP Slovenia in 2012.

At JGP Croatia, she placed second in the short program with a new personal best, once again behind Daria Usacheva. After a strong free skate in which she once again scored a new personal best, she placed first overall with a new personal best overall score of 203.40, more than six points ahead of Usacheva in second and 21 points ahead of Anna Frolova in third. This marked the first time that Lee scored above 200 points in combined total. With two first-place finishes, Lee qualified to the 2019-20 Junior Grand Prix Final as the third-ranked skater, behind Kamila Valieva of Russia and Alysa Liu of the United States. She was the third Korean lady to ever qualify for the final after Kim Yuna and Kim Ye-lim.

At 2020 World Junior Championships in Tallinn, she earned a small silver medal for the short program behind Kamila Valieva earning gold and ahead of Daria Usacheva, who claimed bronze. Lee remarked that she had not expected to be in the top three after the short program, adding "I'm surprised with the score, it’s very high."[3] She also set a new season best for this short program. In the free skate, Lee fell on a downgraded triple flip attempt, resulting in a sixth-place finish in that segment and ranking fifth overall.[4]

With the pandemic greatly curtailing international opportunities for Korean skaters, Kim did not compete on either the Challenger or the Grand Prix circuits, and instead made her competitive debut at the 2021 South Korean Championships. Second in the short program and fourth in the free skate, she won the bronze medal overall. She was assigned to one of Korea's two ladies' berths at the 2021 World Championships in Stockholm, due to silver medalist Yun Ah-sun being age-ineligible for international senior competition.[5]

Lee placed tenth at the World Championships, which, combined with Kim Ye-lim's eleventh place, qualified two berths for Korean ladies at the 2022 Winter Olympics in Beijing.[6][7]

Lee made her senior Grand Prix debut at the 2021 Skate Canada International, where she placed seventh.[8] She was tenth at the 2021 Internationaux de France, her second event.[9] 

At the 2022 South Korean Championships, the final qualification event for the South Korean Olympic team, Lee won the bronze medal, finishing 1.31 points behind silver medalist Kim Ye-lim. As a result, she was not named to one of Korea's two women's berths.[2] All three national medalists were assigned first to compete at the 2022 Four Continents Championships in Tallinn, where Lee placed second in both segments of the competition to take the silver medal, finishing behind Japan's Mai Mihara but ahead of Kim and You Young, the two skaters assigned to the Olympic team. She said that she was "super happy" with the outcome, noting that the event took place in the same arena as the 2020 World Junior Championships where she had missed the podium due to free skate errors.[10]

Lee was assigned to finish her season at the 2022 World Junior Championships in Sofia.[10] It was later announced that she would not be competing, instead intending to compete at the Triglav Trophy.[11] Following Kim's withdrawal from the 2022 World Championships due to a positive COVID test, Lee was named to replace her.[12] She finished in seventh place.[13]

Lee at the 2019–20 Junior Grand Prix Final

Lee at the 2019 World Junior Championships

Small medals for short and free programs awarded only at ISU Championships. Personal bests highlighted in bold.