To meet the technical requirement of on-orbit ground calibration of laser altimeter in the high precision stereo mapping satellite system in China, a laser pulse detector system is developed. The system adopts high-speed PIN detection unit and high-speed data acquisition circuit to realize quantitative acquisition of ns laser pulse, and realizes remote transmission of pulse detector data through radio frequency module. In order to ensure the field application performance of the pulse detector, the energy density test, energy response consistency and stability test, the field of view(FOV) measurement have been carried out for the system. The test results show that the energy acquisition in the range of 1-120 nJ·cm－2 can be accomplished by pulse detector, with the consistency of energy response better than 5% and the stability better than 1.5%, and ±12° FOV can be realized. Finally, the detector has been successfully applied tothe on-orbit calibration of the GF-7 satellite laser altimeter, and the effective laser trigger data of the detector array has been obtained, which provides effective data support for the on-orbit calibration test of the laser altimeter.