CONSTRUCTION MACHINE

On a revolving frame (5), an operating oil tank (15) located on the front side of an engine (8) is provided, and a fuel tank (16) located on the front side of the operating oil tank (15) is arranged. A mounting member (17) is provided on the lower side of the fuel tank (16) across a part of a swing cylinder (14). Between the operating oil tank (15) and the mounting member (17), a vertical restraining element (20) for restraining the fuel tank (16) in a front-rear direction and a vertical direction and a lateral restraining element (25) for restraining the fuel tank (16) in a left-right direction are detachably provided. Therefore, the fuel tank (16) can be restrained in two directions, that is, in the horizontal direction and the vertical direction.