A catheter driving mechanism is developed having two rotors which pinch an aspirate catheter between them and incline to the catheter axis in opposite angle with each other. The two rotors are drove with the same amount of torque in opposite direction to minimize residual torque that devolves on the patient. The driving mechanism showed ability to insert to and draw out a 4mm diameter flexible plastic catheter from a respiratory cannula more than 200mm long with constant speed of about 30mm/s accompanying the rotation of the catheter. The mass of the driving mechanism is about 30g including a joint to a ventilating apparatus and a joint to a vacuum resource for aspiration. Model aspirate tests of 5 kinds of liquid model secretions showed the possibility of aspiration by the driving mechanism developed.