Abstract: On the surface of the Earth, the GPS signal's strength is around-130 dBm. It's vulnerable to interference.And the most important types of interference are the continuous-wave interference.A new continuous-wave interference detection and suppression method is presented.First,this method uses multi-level DFT transform to detect continuous wave interference,and then uses the cascade IIR notch filter to suppress the interferences.Test results show that:When there are -81 dBm continuous wave interferences,this method can detect and suppress these interferences in 3 s,and the GPS receiver's carrier to noise ratio's loss is less than 3 dB.