Intake and exhaust control system and method of diesel engine

The invention discloses an intake and exhaust control system of a diesel engine. The intake and exhaust control system of the diesel engine comprises a flow control part, an acquiring device and a controller, wherein the flow control part is connected between an air storage bottle and an air compressor of a turbocharger, the acquiring device is used for acquiring the air inflow of the air compressor and reflecting state parameters of air demanding quantity of an air cylinder of the diesel engine, and the controller is connected with the acquiring device and is used for acquiring the air demanding quantity of the air cylinder according to the state parameters and controlling the size of an opening of the flow control part according to the air inflow and the air demanding quantity to enable the total air inflow of the air compressor after air supplement to be equal to the air demanding quantity. According to the intake and exhaust control system of the diesel engine, when the diesel engine operates slowly, the air compressor can convey sufficient air to the air cylinder after being supplied with air by means of the air storage bottle, so that oil burning of the air cylinder is achieved fully, large torque is generated, oil consumption is reduced, and exceeding discharging is avoided. The invention further discloses an intake and exhaust control method corresponding to the control system.