Sojin worked as a vocal trainer for the South Korean boy band Ulala Session prior to her debut with Girl’s Day in July 2010. In March 2013, the girl group released their first studio album called Expectation, which was re-released under the title Female President. In 2014, the song Something from their fourth extended play Everyday 3 became their highest-charting single, peaking at No. 2 on both the Billboard’s K-Pop Hot 100 and the Gaon Digital Chart. The single’s music video also reached over a million views in just one day. In 2015, Girl’s Day ranked 13th in Forbes Korea’s Power Celebrity List.

Sojin made her acting debut in 2011 with a cameo appearance in the MBC series I Trusted Him. She then played supporting characters in TV Chosun’s Greatest Marriage in 2014 and in SBS’s The Family Is Coming in 2015. In 2020, she became part of the SBS series The King: Eternal Monarch and the MBC drama The Spies Who Loved Me. Her work in the latter earned her a Best New Actress nomination at the MBC Drama Awards. In 2022, she joined the main cast of the tvN romantic comedy Shooting Stars.

Sojin majored in mechanical engineering at Yeungnam University. She dated singer-songwriter Eddy Kim. In November 2023, she married actor Lee Dong-ha in a private ceremony in Seoul.