A hydraulic excavator includes a cab disposed on a front portion of a revolving upper structure. An internal combustion engine is mounted in a rear portion of the revolving upper structure, and an directional control valve is disposed in the front portion of the revolving upper structure at a position spaced laterally from the cab. The directional control valve is arranged longitudinally of the revolving upper structure. A hydraulic oil tank and a fuel tank for the internal combustion engine are disposed on either side of the directional control valve. By virtue of a space provided between the directional control valve and the cab, transmission of heat and operation noise from the directional control valve to the cab is greatly suppressed.