Kim Gap-soo made his acting debut in 1977 and has since become a staple in television dramas and films. In 1990, he received the Best New Actor for TV trophy at the 26th Baeksang Arts Awards for his work in the KBS1 series And So Flows History. In 1994, he starred in the movie The Taebaek Mountains, in which he won Best Actor at the 31st Baeksang Arts Awards and the 33rd Grand Bell Awards. In 2003, he took home the Best Supporting Actor trophy at the 4th Busan Film Critics Awards for his work in the film Mutt Boy. In 2010, he earned a Top Excellence Award at the KBS Drama Awards for his performance in the well-loved dramas Sungkyunkwan Scandal, Cinderella’s Sister, and Chuno. That same year, he was named Most Influential Star at the 4th Mnet 20’s Choice Awards. In 2011, he led the MBC sitcom All My Love, in which he bagged a Top Excellence Award at the MBC Entertainment Awards.

Kim Gap-soo has his own master-class acting studio. He has been married since 1986.