A non-commissioned officer underwent gender reassignment surgery last year during a vacation overseas and the Army will now deliberate on whether to discharge the person from the military.
The individual has reportedly expressed her desire to continue serving as a female soldier.
This is the first time in the nation's military history that an active-duty service person had a sex change operation and intends to continue serving in the armed forces.
According to Army sources on Thursday, the staff sergeant serving in a unit in northern Gyeonggi Province had the surgery abroad last year and has returned home and is now checked into an armed forces hospital.
The Army will hold a deliberations committee meeting next Wednesday.
Under current law, no specific rule exists on whether to allow those who change their gender while in the military to continue their service.