He studied at Seoul Arts University and debuted as an actor in 1998.
In January 2010, he married his long-time fan, who had dated him since 2005.
On May 9, 2020, his dog, which had a history of attacking people and was not leashed even after numerous complaints, attacked a woman in her 80s resulting in her death. In response, Kim Min-kyo posted an apology on SNS but did not apologize to the family members directly.
On March 23, 2022 has been sentenced to a probationary period of 2 years. If the commits a similar crime during his probationary period, he will face a minimum of 8 months in prison.