The invention provides an upper injection receiving processor simulator of a navigation satellite. The upper injection receiving processor simulator of the navigation satellite comprises an analog signal processing unit and a digital signal processing unit, wherein the analog signal processing unit is used for performing down-conversion on an upper injection radio frequency signal to an analog intermediate frequency signal by completing radio frequency signal down-conversion, digital-to-analog conversion and data transmission, then converting the analog intermediate frequency signal into a digital intermediate frequency signal, and transmitting the digital intermediate frequency signal to the digital signal processing unit after packaging the digital intermediate frequency signal; and thedigital signal processing unit is used for receiving the digital intermediate frequency signal based on GPU operation, and processing the digital intermediate frequency signal so as to simulate the receiving of an uplink injection signal when a satellite operates.