Abstract: Global Navigation Satellite System (GNSS) has been widely used in various military and civil systems. But the GNSS signal is weak, and the format of civil signal is open, so it is extremely vulnerable to various electromagnetic interference. For GPS L1 C/A code, the noise higher than −160 dBm/Hz will affect the acquisition of the receiver. But generally, the sensitivity of spectrum interference monitoring equipment is −150 dBm/Hz and cannot detect the weak interference. This paper proposed methods that utilize the information of automatic gain control (AGC), carrier to noise ratio (\rmC/N_0) and position of the general receiver to realize jamming and spoofing detection and identification. The methods were tested by setting up a real environment and the results showed that the methods in this paper can detect and identify GNSS jamming and spoofing. The detection accuracy can reach 96%, and the identification accuracy of jamming and spoofing can reach 94%.