Go Sung-hee started out her entertainment career as a host of Elle TV’s variety show Style Studio in 2009. She was an idol trainee under KeyEast Entertainment but left to pursue acting. In 2010, she had a minor role in the movie A Good Night Sleep for the Bad. In 2013, she was cast in the MBC series Miss Korea. The following year, she landed her first leading role in the MBC fantasy sageuk drama Records of a Night Watchman. Go Sung-hee brought home the Best New Actress trophy at the 2014 MBC Drama Awards for her performance in the two dramas. In 2017, she was nominated for an Excellence Award at the SBS Drama Awards for the romantic fantasy series While You Were Sleeping. In 2018, she collected Best Supporting Actress nominations for her work in the dramas Mother, Suits, and Ms. Ma, Nemesis. In 2020, she took on the lead role in the romantic science fiction Netflix series My Holo Love, opposite Yoon Hyun-min.
Go Sung-hee is also an American citizen having born in the United States. Aside from Korean, she is also fluent in English. In November 2022, she married her non-celebrity boyfriend.