To address the challenge of autonomous orbiting of space satellites under the increasing number of satellites in space,the Satellite Tool Kit (STK) is used to simulate and analyze the orbiting of medium-orbit satellites under Multi-Global Navigation Satellite System (Multi-GNSS) signals. The four global navigation systems and augmentation systems are modeled by STK. The satellite signals from the navigation systems are received by the middle earth orbit (MEO) satellite. The satellite signals from the navigation systems are received by the middle earth orbit (MEO) satellite receiver, and the number of visible stars, the Dilution of Precision (DOP) value, and the navigation and positioning accuracy are used as the evaluation indexes. The navigation systems are received by the middle earth orbit (MEO) satellite receiver, and the number of visible stars, the Dilution of Precision (DOP) value, and the navigation and positioning accuracy are used as the evaluation indexes to study the optimal positioning mode of the middle-orbit satellites in the case of multi-GNSS. concluded that under single-system positioning, the positioning accuracy of BEIDOU system is higher, up to 4 meters accuracy. Under dual-system positioning, the combined accuracy of BEIDOU system is higher, up to 4 meters accuracy. Under dual-system positioning, the combined accuracy of BEIDOU and the Global Positioning System (GPS) is higher, with an accuracy of about 3 meters.