An intelligent bionic expectoration system and a three-way device thereof. The intelligent bionic expectoration system includes a negative pressure suction module, a central processing module, a patient interface unit and a respiratory muscle synchronous motion module. The central processing module controls two valves to open or close, closing one valve while opening another valve, and controls the respiratory muscle synchronous motion module. The patient interface unit is connected to the positive pressure ventilation module and the negative pressure suction module, allowing positive or negative pressure airflow to flow by, depending on which valve is open, so as to allow airflow to flow in or out of the lung. The respiratory muscle synchronous motion module can employ nerve stimulation and mechanical pushing, and acts synchronously as the airflow moves, thereby simulating human coughing and achieves bionic expectoration.