To provide an open type push-pull ventilator capable of selecting optionally a size of a push hood, and capable of designing optionally a wind volume to be matched to the size of the push hood.

This open type push-pull ventilator is installed with a hood body 4 and an axial fan 5 respectively in an upper frame 2 and a lower frame 3. The hood body 4 is provided with a punching metal 14 and metal nets 15, 16 on its front face, and is provided with an air supply port 10 for air supplied from the axial fan 5 on is bottom face. Guide vanes 12, 13 and an inner screen 17 are provided in an inside of the hood body 4. An air flow of a peripheral part is delivered to an outside via the inner screen 17, and the punching metal 14 and the metal nets 15, 16 on its front face, and an air flow of the central part is delivered to the outside via the punching metal 14 and the metal nets 15, 16 on its front face.