To provide a construction machine control system which has high working easiness, can detect a reference plane with a simple and inexpensive configuration, and can measure the height of the reference plane and the height of an operation position.

The construction machine control system comprises a rotation laser device 1 having a communication device 11, a laser beam irradiating part which has a light receiving part for receiving reflection light of laser beams, forms a laser beam reference plane by scanning the laser beams 4 and can incline the laser beams reference plane, and an inclination detecting part which detects the inclination of the laser beam irradiating part; and a construction machine 2 having a ground leveling instrument 6, a target 5 which is provided with the ground leveling instrument to reflect the laser beams, a drive control part which controls the height of the ground leveling instrument, a transmission/reception part 77, and a GPS position measuring device which detects the position of a construction machine.