The invention discloses a distributed control system of a glass magnesium board production line and a control method thereof. The distributed control system of a glass magnesium board production line includes an upper computer IPC, a template on-line control unit, a board conveying control unit, a batching stirring control unit, and a board forming control unit. unit, plate cutting control unit, and plate entering cage control unit. The upper computer IPC serves as the master station of Modbus, and each control unit serves as the slave station of Modbus, which together constitute the distributed control system of the glass magnesium board production line. The upper computer IPC is responsible for the data exchange between each control unit to ensure the coordinated work of each control unit; each control unit includes a PLC and a touch screen, under the coordination of the upper computer IPC, realize the control of their respective units. The invention adopts distributed control, integrates technologies such as industrial bus technology, advanced sensor technology, PID technology and remote monitoring into the control system, and has a high degree of automation.