He got COVID-19 in February and was sent to the facility Sunday. He was found dead Wednesday.
He had earlier been charged with flouting South Korea's quarantine guidelines.
A 37-year-old South Korean man is said to have died by suicide in a South Korean COVID-19 treatment facility, after being charged with violating the country's strict laws on quarantining and self-isolating, according to Yonhap News.
The man, known to authorities as "A," had contracted COVID-19 in February and was sent to the facility Sunday.
He was found unconscious in his room at the Yeongjong treatment facility in Incheon, a city just outside Seoul, on Wednesday.