Abstract: A refrigeration cycle device includes: a casing that configures the outer contour of an outdoor machine, has a machine chamber and a blowing chamber formed therewithin, and has formed an introduction hole for introducing outside air into the machine chamber; a partition plate that partitions the interior of the casing so as to demarcate the machine chamber and the blowing chamber; a refrigeration cycle circuit, of which at least a portion is disposed in the machine chamber, and through which a combustible refrigerant circulates; and a blower disposed in the blowing chamber. A blow-through hole connecting from the machine chamber to the blowing chamber is formed in a bottom part of the partition plate. The outside air introduced into the machine chamber from the introduction hole flows through the blow-through hole and into the blowing chamber, and is sent outside the casing from a blow-out opening formed in the blowing chamber.