To provide a liquid spout device of a construction machinery in which a worker can easily open/close a cap even when the cap of a spout is heated, or a spout can be easily distinguished and identified even when a plurality of spouts are installed.

A cap cover which is fitted so as to be opened/closed together with a cap is provided on the cap which is mounted on a spout in a freely openable/closable manner by the manual operation. The cap cover prevents the heat of the cap from being transferred to a hand to perform the opening/closing operation, and the spouts can be easily distinguished and identified by changing the color of the cap cover.