To prevent the mounting direction, attitude, and position of an electronic controller, in an engine room or the like from being regulated in the electronic controller, having a waterproof case provided with a breath filter.

The electronic controller is provided with a protective wall 60, which is erected so as to surround the arrangement part of the breath filter 50, and at least two or more drainage recesses 70, respectively opened at mutually different positions on the protective wall 60.