A pneumatic control device of auto door, comprising: a first directional control valve configured to control a direction of a compressed air supplied to a door cylinder for opening and closing a door; and first and second exhaust lines (L31, L32) respectively connected to first and second outlet ports (TA, TB) of the first directional control valve; characterized in that the device further comprises a door detection sensor (44A, 44B) configured to detect an open/close state of the door; second directional control valves (140, 142) installed in the first and second exhaust lines respectively to operably exhaust the compressed air exhausted from the first and second outlet ports (TA, TB) according to an emergency stop signal, and capable of changing positions to reduce an exhaust speed of the compressed air; and a controller configured to receive signals from the door detection sensor (44A, 44B) and output control signals to the first directional control valve and the second directional control valves (140, 142) respectively to control operations thereof, wherein the controller outputs the control signal for opening and closing the door to the first directional control valve to supply the compressed air to the door cylinder through the first directional control valve, wherein the controller outputs the control signal for stopping the operation of the door to the first directional control valve to stop the supply of the compressed air and outputs the control signal for exhausting the compressed air to the second directional control valves (140, 142) to exhaust the compressed air from the first and second outlet ports (TA, TB) through the second directional control valves (140, 142) according to the emergency stop signal, and wherein the controller switches the second directional control valves (140, 142) to reduce the exhaust speed of the compressed air in case that the door is not completely open or closed when an operation signal is generated after the emergency stop signal. a first directional control valve configured to control a direction of a compressed air supplied to a door cylinder for opening and closing a door; and first and second exhaust lines (L31, L32) respectively connected to first and second outlet ports (TA, TB) of the first directional control valve; characterized in that the device further comprises a door detection sensor (44A, 44B) configured to detect an open/close state of the door; second directional control valves (140, 142) installed in the first and second exhaust lines respectively to operably exhaust the compressed air exhausted from the first and second outlet ports (TA, TB) according to an emergency stop signal, and capable of changing positions to reduce an exhaust speed of the compressed air; and a controller configured to receive signals from the door detection sensor (44A, 44B) and output control signals to the first directional control valve and the second directional control valves (140, 142) respectively to control operations thereof, wherein the controller outputs the control signal for opening and closing the door to the first directional control valve to supply the compressed air to the door cylinder through the first directional control valve, wherein the controller outputs the control signal for stopping the operation of the door to the first directional control valve to stop the supply of the compressed air and outputs the control signal for exhausting the compressed air to the second directional control valves (140, 142) to exhaust the compressed air from the first and second outlet ports (TA, TB) through the second directional control valves (140, 142) according to the emergency stop signal, and wherein the controller switches the second directional control valves (140, 142) to reduce the exhaust speed of the compressed air in case that the door is not completely open or closed when an operation signal is generated after the emergency stop signal.