Abstract: An evaporative cooler is efficiently constructed of molded plastic materials, with a minimum of parts and simplicity in assembly. A blower shroud of a squirrel cage type blower extends the height of the cooler unit interiorly, and is secured by fasteners to a top panel and a base panel. Four side panels with air inlet openings are secured at their edges to the top and bottom panels. Water-retaining material is secured to the inside of each side panel, and the top edge of each side panel forms a water trough for dripping water down into the water-retaining material to be evaporated as air enters the unit. The water is circulated by a pump which draws collected water from a basin in the base panel and delivers it to the troughs.