The invention relates to a upper barrel suitable for the device to kill mosquitoes and/or flies. The upper barrel comprises a first external shell, a circuit controlling board, an actuator and a pillar, the actuator includes a first and second electric motor with drive mechanism, a first and second wire rewinding wheel, each axis of the motors is vertical to each other. The rotation of the wheels in the upper barrel drives the middle barrel moving up and down, mosquitoes and/or flies are attracted to the device when the middle barrel is drived to the top portion by the rotation of the wheel, and pressed under water to be drown when the middle barrel is drived to the bottom portion by the rotation of the wheel, the killing course do not cause secondary pollution or threat to health.<；Figure 17>；
