The invention discloses a high precision microwave transmission line installation calibration tool and an installation calibration process thereof. The installation calibration tool includes high precision calibration tools, a laser tracker and at least one microwave transmission section. The high precision calibration tools are installed on both ends of the microwave transmission section. The high precision calibration tools are equipped with laser tracker targets. The laser tracker is connected to the laser tracker targets via signals. The laser tracker creates a model of all the microwave transmission segments under a unified system reference network with positions of the microwave transmission segments in the space and parameters in a three-dimensional reference network, and positions each of the microwave transmission sections in the entire microwave transmission system to system positions. The installation calibration process includes the steps of establishing a standard coordinate system and the like. According to the invention, under the premise of ensuring the entire system precision, the overall progress of a microwave transmission waveguide is controlled on the global and macroscopic scale, the system error caused by the installation of the waveguide transmission line can be effectively calibrated, and the advantages of convenient installation and strong applicability are also gained.