Kim Young-ok began her decades-long career in the entertainment industry in 1957 with an appearance in the film Farewell Sorrow. In 1961, she debuted as a voice actor for the newly established Munhwa Broadcasting Corporation or MBC. In 1978, she starred in the MBC series I Sell Happiness, which won her the Daesang at the 15th Baeksang Arts Awards. In 1992, she was named Baeksang Most Popular Actress for TV for the KBS2 drama Yesterday’s Green Grass. The following year, she received a Top Excellence Award at the KBS Drama Awards for her work in Wild Chrysanthemum and Love and Farewell. In 2005, she played a foul-mouthed grandmother in the popular KBS2 daily series Old Miss Diary, which earned her an Achievement Award at the KBS Drama Awards. Its film adaptation, meanwhile, scored her a Best Supporting Actress nomination at the 44th Grand Bell Awards. In 2009, she took home a Golden Acting Award at the MBC Drama Awards for the family series Assorted Gems. In 2011, she was presented with another Achievement Award at the SBS Drama Awards for Protect the Boss. In 2015, she portrayed a comfort woman in the KBS1 period drama special Snowy Road, which gave her an Excellence Award at the KBS Drama Awards.

Kim Young-ok and her husband named Kim Young-gil tied the knot in 1960.