To provide a device that suppresses power consumption and improves use efficiency when a domestic air conditioner is used in a normal manner.

A water spraying cooler is attached to a heat exchange fin of the rear face of an outdoor machine by a fixation plate 8 in a state where a longitudinal side runs along an outdoor machine side so that a tip part 6 of a water spraying filter 5 can be closely contacted uniformly. In the water spraying coller, a cooler body 1 is a rectangular box body and is provided with a water filler 2 on the top face, a tip part of a water spraying filter having the substantially same width as that of a longitudinal one side 3 is projected from an opening part 4 provided in the vicinity of the longitudinal one side 3, and a water storage part 7 is provided in the box body.