Moon Ga-young started her career in 2006 as a child actress. In 2010 and 2013, she was nominated for Best Young Actress at the KBS Drama Awards for her work in The Reputable Family and King’s Family, respectively. In 2014, she landed her first leading role in the four-episode Mnet series Mimi. In 2016, she played a supporting role in the hit SBS workplace romantic comedy Jealousy Incarnate. This was followed by another supporting role in the tvN time-slip drama Live Up to Your Name in 2017. In 2018, she became part of the main cast of the MBC romance drama The Great Seducer, which won her an Excellence Award at the MBC Drama Awards. In 2020, she bagged a Top Excellence Award nomination at the MBC Drama Awards for her performance in Find Me in Your Memory. That same year, she was cast to play the female lead role in the tvN series True Beauty.

Moon Ga-young is fluent in German, having lived in Germany for 10 years. She majored in acting and arts at the Sungkyunkwan University.