[2] Kang made her acting debut in the 2009 thriller movie 4th Period Mystery, but rose to fame when she starred in the 2011 blockbuster Sunny, a coming-of-age film about a group of high school girls growing up in the 1980s.

[8][9] Kang gained increased recognition after starring in two hit series in 2014: medical drama Doctor Stranger (2014)[10][11] and workplace dramedy Misaeng: Incomplete Life (2014).

[12] Doctor Stranger was a success in China with 400 million views, and Misaeng: Incomplete Life was dubbed a "cultural phenomenon" in South Korea.

[13][14] This was followed by lead roles in romantic comedy Warm and Cozy (2015) together with Yoo Yeon-seok,[15][16] legal drama My Lawyer, Mr. Jo (2016),[17] and romantic comedy Revolutionary Love (2017) alongside Choi Si-won from the k-pop group Super Junior.

[22] Kang married a doctor of Oriental medicine in August 2020 in a private ceremony.