A master-slave control method based on the identifications of load force and impedance for Tele-operated hydraulic construction robot system is presented in this paper. The robot system is composed of a hydraulic excavator and two joysticks. The hydraulic excavator is served as the construction robot. The joysticks are used for operating the robot in a remote region. The master actuator and the slave actuator in this system are the joystick-gear of a joystick and the fork-glove actuator of the excavator respectively. The load force and impedance identifiers are used for identifying the load force and impedance of the slave actuator respectively. According to the load force, the master controller controls the master actuator to generate the reaction force for operator. On the basis of the load impedance and the master slave error, the slave controller controls the slave actuator to perform a working task. The experimental researches confirmed that the operator not only obtains the force sense of the object accurately, but also obtains the deformation and stiffness senses of the object obviously.