In order to calibrate the range accuracy of the laser rangefinder，a calibration system of the laser rangefinder is designed. The system is mainly composed of attenuation components and ranging precision simulator. A ranging precision simulator based on photoelectric delay simulation method is designed. The output laser of the laser diode is divided by the beam splitting prism，and the output laser signal is measured by the TDC module with picosecond time measuring accuracy. The uncertainty error caused by the clock is reduced，and the delay generated by the optical path and the circuit cancles each other，which improves the simulation distance accuracy. The ranging precision simulator has been tested by the national legal metrology technical institution and meets the design requirements. The measuring accuracy of a laser rangefinder is calibrated and verified by the designed calibration system. The results show that the device can calibrate the measuring accuracy of the laser rangefinder，and the measuring repeatability is less than 1.0 m. The ranging precision simulator can be used as standard measuring equipment.