A construction machine comprising: a vehicle body (2, 4) on which an operator gets; an engine that is mounted on said vehicle body (2, 4); an exhaust gas purifying device that is provided in an exhaust side of said engine and traps particulate matter in an exhaust gas discharged from said engine by a filter; a regeneration device that burns the particulate matter trapped in said filter to execute regeneration treatment of said filter; a state detecting device formed of a plurality of kinds of detectors for detecting working states of said engine, said exhaust gas purifying device and said regeneration device; and a control device for performing control of said engine and said regeneration device based upon a detection value of each of the detectors forming said state detecting device, characterized in that: said state detecting device includes differential pressure detectors (35, 36) for detecting a differential pressure that is a difference between a pressure in an inlet side and a pressure in an outlet side of said filter in said exhaust gas purifying device, and said control device comprises: a trouble determining unit configured to determine whether any of said differential pressure detectors (35, 36) forming said state detecting device has a trouble or a detector other than said differential pressure detectors (35, 36) has a trouble; an excessive accumulation determining unit configured to determine whether or not the particulate matter is excessively accumulated in said filter based upon the differential pressure detected by said differential pressure detectors (35, 36) in a case where it is determined that said detector other than said differential pressure detectors (35, 36) has the trouble by said trouble determining unit; and an operation restricting unit configured to, in a case where it is determined that said detector has the trouble by said trouble determining unit, and/or it is determined that the particulate matter is excessively accumulated in said filter by said excessive accumulation determining unit, alarm an operator of the trouble and/or restrict output of said engine. a vehicle body (2, 4) on which an operator gets; an engine that is mounted on said vehicle body (2, 4); an exhaust gas purifying device that is provided in an exhaust side of said engine and traps particulate matter in an exhaust gas discharged from said engine by a filter; a regeneration device that burns the particulate matter trapped in said filter to execute regeneration treatment of said filter; a state detecting device formed of a plurality of kinds of detectors for detecting working states of said engine, said exhaust gas purifying device and said regeneration device; and a control device for performing control of said engine and said regeneration device based upon a detection value of each of the detectors forming said state detecting device, characterized in that: said state detecting device includes differential pressure detectors (35, 36) for detecting a differential pressure that is a difference between a pressure in an inlet side and a pressure in an outlet side of said filter in said exhaust gas purifying device, and said state detecting device includes differential pressure detectors (35, 36) for detecting a differential pressure that is a difference between a pressure in an inlet side and a pressure in an outlet side of said filter in said exhaust gas purifying device, and a trouble determining unit configured to determine whether any of said differential pressure detectors (35, 36) forming said state detecting device has a trouble or a detector other than said differential pressure detectors (35, 36) has a trouble; an excessive accumulation determining unit configured to determine whether or not the particulate matter is excessively accumulated in said filter based upon the differential pressure detected by said differential pressure detectors (35, 36) in a case where it is determined that said detector other than said differential pressure detectors (35, 36) has the trouble by said trouble determining unit; and an operation restricting unit configured to, in a case where it is determined that said detector has the trouble by said trouble determining unit, and/or it is determined that the particulate matter is excessively accumulated in said filter by said excessive accumulation determining unit, alarm an operator of the trouble and/or restrict output of said engine.