A construction machine comprising: an automotive vehicle body (2, 3); a working mechanism that is tiltably provided in a front portion side of said vehicle body; a cab that is positioned in the left side of said working mechanism and is provided in a front portion side in said vehicle body to define an operator's room; a right front housing cover that is positioned in the right side of said working mechanism and is provided in a front portion side in said vehicle body and within which a valve accommodation room is formed; a hydraulic pump (37, 39) that is mounted on said vehicle body to deliver pressurized oil toward a plurality of hydraulic actuators; and an operation device that is provided in said cab to be operated by an operator for driving said respective hydraulic actuators, wherein a first control valve that is configured of a collector of a plurality of directional control valves (24, 25, 26, 27, 28, 29) to control a flowing direction of the pressurized oil to be supplied to said respective hydraulic actuators from said hydraulic pump (37, 39), a second control valve that outputs an operation signal output to said directional control valves (24, 25, 26, 27, 28, 29) of said first control valve from said operation device, and a third control valve that controls hydraulic equipment including said hydraulic actuator and said hydraulic pump (37, 39), are provided in said right front housing cover, characterized in that: said first control valve is arranged in a front portion side in said valve accommodation room, said second control valve is arranged in the back side of said first control valve and in the upper side of said first control valve, said third control valve is arranged in the back side of said second control valve, and said right front housing cover is provided along a virtual line (B-B) extending in an oblique downward direction through a front end of said first control valve and a front end of said second control valve. an automotive vehicle body (2, 3); a working mechanism that is tiltably provided in a front portion side of said vehicle body; a cab that is positioned in the left side of said working mechanism and is provided in a front portion side in said vehicle body to define an operator's room; a right front housing cover that is positioned in the right side of said working mechanism and is provided in a front portion side in said vehicle body and within which a valve accommodation room is formed; a hydraulic pump (37, 39) that is mounted on said vehicle body to deliver pressurized oil toward a plurality of hydraulic actuators; and an operation device that is provided in said cab to be operated by an operator for driving said respective hydraulic actuators, wherein said first control valve is arranged in a front portion side in said valve accommodation room, said second control valve is arranged in the back side of said first control valve and in the upper side of said first control valve, said third control valve is arranged in the back side of said second control valve, and said right front housing cover is provided along a virtual line (B-B) extending in an oblique downward direction through a front end of said first control valve and a front end of said second control valve.