The Oklahoma County Detention Center said a 22-year-old man was discovered unresponsive on Wednesday morning.
Detention center officials said Parker Stephens was found around 9:20 a.m. Wednesday.
The jail's medical staff and EMSA were alerted, but Stephens was pronounced dead by the Oklahoma City Fire Department.
A detention center spokesperson said the medical examiner will determine Stephens' cause of death while the jail's investigation unit will also conduct an investigation.
Stephens' death is the third known death at the jail since the start of 2021 and the sixth death over the last seven weeks.