Eom Ki-joon made his acting debut in the 1995 stage play Richard III and then went on to star in various theater productions. His first TV roles include appearances in several episodes of the KBS program Drama City. He won the Best Supporting Actor trophy at the 2008 KBS Drama Awards for the romantic drama series Worlds Within. He was also nominated for Best New Actor for TV at the 45th Baeksang Arts Awards for his role in the drama. He made his big screen debut in the 2010 movie Man of Vendetta, in which he was nominated for Best New Actor for Film at the 47th Baeksang Arts Awards. In 2011, he took home an Excellence Award at the SBS Drama Awards for his performance in the romantic drama series Scent of a Woman. In 2017, he earned the Character of the Year award at the SBS Drama Awards for his role as the main villain in the hit legal thriller Defendant. In 2020, he starred in the megahit SBS series Penthouse. His portrayal of a scheming real estate genius in the drama won him a Top Excellence Award at the 2020 SBS Drama Awards. He was also nominated as Best Actor for TV at the 57th Baeksang Arts Awards for his work in the series.
In July 2011, Eom Ki-joon was involved in a car accident, where he rear-ended a taxi while allegedly driving under the influence. No one was greatly injured in the accident.