The Chairman of the Joint Chiefs of Staff position in military command structure
Assistance to the National Defense Minister on military commands
National Armed Forces Organization Act Article 9 Paragraph 2 defines that "The Chairman of the Joint Chiefs of Staff assists the National Defense Minister on military commands..."
The Chairman of the Joint Chiefs of Staff's duty of assistance includes assisting the Minister of National Defense in his/her exercise of all military command authority
Authority to command and supervise operations forces and joint forces
The Chairman of the Joint Chiefs of Staff Commands and supervises military's combat operations of each branch pursuant to instructions of the Minister of National Defense.(National Armed Forces Organization Act Article 9 Paragraph 2, National Armed Forces Organization Act Article 9 Paragraph 3 regarding regulations on combat operations forces of each Services)
The Head of the Joint Chiefs of Staff
The Chairman of the Joint Chiefs of Staff has the authority as the head of the Joint Chiefs of Staff in accordance with Article 12 of National Armed Forces Organization Act and a Presidential Decree concerning Organization of the Joint Chiefs of Staff
Advice for National Security Council(NSC) and the Minister of National Defense
The Chairman of the Joint Chiefs of Staff serving as a chief military advisor for the Minister of National Defense pursuant to Article 9 of National Armed Forces Organization Act also executes advisory functions regarding military matters through a direct participation in NSC in accordance with National Security Council Act
Execution of Duty as Director of Integrated Defense Headquarters
The Chairman of the Joint Chiefs of Staff extablishes guidelines and pans for united defense operations, and inspects and supervises the preparedness for united defense in order to provide against an enemy infiltration, provocation, or threats in accordance with Artile 8 of Integrated Defense Act
Execution of Duty as Martial Law Commander
The Chairman of the Joint Chiefs of Staff, appointed by the president in accordance with martial law, acts as a martial law commander when the social order is so disturbed that civil administrative authority is not capable of performing the administrative functions and preserving the public peace in time of war, incident or similar national emergency
Others
The Chairman of the Joint Chiefs of Staff has been conferred the power to decide upon the requirements for weapons systems under Article 15 of the Defense Acquisition Program Act, and to make a recommendation to designate, modify or cancel military protection zones under Article 4 of the Protection of Military Bases and Installations Act