Yoo Inna became a trainee singer at age 16 and was once on the verge of debuting in a girl group. But due to having difficulties learning dance choreographies, she decided to pursue acting instead. In 2009, she made her acting debut in the MBC sitcom High Kick through The Roof. In 2011, she won Best New Actress at the 47th Baeksang Arts Awards for the hit SBS series Secret Garden. Also in 2011, she became part of the main cast of the MBC romantic comedy Best Love, which earned her Best New Actress nomination at the MBC Drama Awards. In 2012, she landed her first leading role in tvN’s Queen In-hyun’s Man, opposite Ji Hyun-woo. In 2013, she widened her popularity after appearing in the widely successful SBS fantasy romantic comedy You From Another Star. In 2016, she was cast in the top-rating tvN drama The Lonely Shining Goblin. In 2019, she reunited with her The Lonely Shining Goblin co-star Lee Dong-wook in the tvN romantic comedy Reach of Sincerity, which gave her an Excellence Award nomination at the 12th Korea Drama Awards. In 2020, she was nominated for a Top Excellence Award at the MBC Drama Awards for her performance in The Spies Who Loved Me.

Aside from acting, Yoo Inna also served as the DJ of the radio show Let’s Crank Up the Volume from 2011 to 2016. Her work in the radio program won her the Best Radio DJ trophy at the 2014 KBS Entertainment Awards.

On June 18, 2012, Yoo Inna confirmed her relationship with her Queen In-hyun’s Man co-star Ji Hyun-woo. The confirmation came after Ji Hyun-woo publicly declared his love for her during a fan meeting for the TV series. The couple parted ways in 2014. Yoo Inna is close friends with singer and actress IU.