D.O. was introduced as a member of EXO on January 30, 2012. The group officially made their debut on April 8 with the EP Mama. Their breakthrough came in 2013 with the release of their debut studio album XOXO, which spawned the hit single Growl. EXO’s single Monster from their third studio album Ex’Act became the group’s first number one on the Billboard World Digital Songs chart. The group topped Forbes Korea’s Power Celebrity List for two consecutive years in 2015 and 2016. In 2018, the group released their sixth studio album titled Don’t Mess Up My Tempo, which debuted at number 23 on the U.S. Billboard 200.

D.O. debuted as an actor in the 2014 movie Cart, in which he scored a Best Supporting Actor nomination at the 52nd Grand Bell Awards. That same year, he landed his first small screen role in the SBS series It’s Okay, It’s Love, which won him Best New Actor at the 3rd APAN Star Awards. He then bagged back-to-back Most Popular Actor for Film trophies at the 52nd and 53rd Baeksang Arts Awards for his work in the movies Pure Love and My Annoying Brother. His performance in the latter also earned him Best New Actor citation at the 38th Blue Dragon Film Awards. In 2018, he picked up another Best New Actor trophy at the 18th Director’s Cut Awards for the movie Along with the Gods: The Last 49 Days. Also in 2018, he headlined the hit tvN sageuk 100 Days My Prince, opposite Nam Ji-hyun. He was named Most Popular Actor for TV at the 55th Baeksang Arts Awards for his work in the series.

D.O. enlisted for his mandatory military service on July 1, 2019. He was discharged on January 25, 2021.