Laser target simulator is widely used in the test of laser guidance system. The simulated orientation of laser signal source can be deviated from the design index greatly in the long-term use, and the laser guidance system should be calibrated and tested on site. Firstly, the principle of laser target simulator is analyzed in detail, and then the design scheme of laser target simulator calibration device is expounded respectively from the aspects of hardware and software design. The test results indicate that the parameters of laser signal simulation light source such as azimuth, emission angle and signal power can be accurately measured and verified by the device and the performance indexes meet the use requirements.