Kwon So-hyun debuted with the short-lived child group Orange in 2005. That same year, they released their debut album We Are Orange prior to their disbandment. Kwon So-hyun later debuted with the girl group 4Minute in 2009 with the single Hot Issue. In 2010, they dropped their debut Japanese studio album Diamond, which was followed by the release of their first Korean studio album 4Minutes Left in 2011. Aside from their full-length albums, the group also has seven extended plays and a compilation album under their belt.

Prior to her debut as a singer, Kwon So-hyun had cameo roles in several television dramas such as MBC’s Dae Jang Geum and SBS’s Lovers in Paris in 2003 and 2004. In 2017, she had a brief appearance in the tvN series Criminal Minds. In 2019, she played supporting characters in the SBS romantic comedy The Secret Life of My Secretary and in OCN’s Class of Lies. She also became part of the 2019 drama film Birthday. In 2022, she joined the KBS2 sports romance drama Love All Play.

Kwon So-hyun graduated from Seoul’s Pungmoon Girls’ High School and was later accepted to Dongguk University.