A data processing method for a multi-channel multistatic Synthetic Aperture Radar, SAR, stationary receiver, the multi-channel multistatic SAR stationary receiver comprising an antenna unit, a radio frequency unit, a detection unit, and a data collection unit, the method comprising: at the antenna unit, receiving one channel of radio frequency signal from a transmitter and N channels of echo signals fed back from a target area, and sending the one channel of radio frequency signal and the N channels of echo signals to the radio frequency unit, wherein N is an integer larger than 1; at the radio frequency unit, equally splitting the one channel of radio frequency signal into N+1 channels of direct signals, demodulating one of the N+1 channels of direct signals to an intermediate frequency signal, sending the intermediate frequency signal to the detection unit, and sending the other N channels of direct signals of the N+1 channels of direct signals that are used as reference signals of the N channels of echo signals respectively and the N channels of echo signals to the data collection unit; at the detection unit, detecting the intermediate frequency signal in a time domain, generating a rising edge trigger signal when detecting a pulse signal in the intermediate frequency signal, amplifying the rising edge trigger signal and sending the amplified rising edge trigger signal to the data collection unit; at the data collection unit, collecting the N channels of direct signals and the N channels of echo signals, upon reception of the rising edge trigger signal from the detection unit, wherein the detecting the intermediate frequency signal in a time domain and generating a rising edge trigger signal comprises: at the detection unit, performing Analog/Digital, A/D, sampling on the intermediate frequency signal in the time domain to obtain a sequence of discrete digital signals; at the detection unit, performing digital signal mixing, low pass filtering, down-sampling and sliding envelope detection on the sequence of discrete digital signals, to obtain a detection result; at the detection unit, comparing the detection result with a preset threshold value, and generating the rising edge trigger signal when the detection result is larger than or equal to the preset threshold value, wherein the sliding envelope detection comprises: at the detection unit, performing periodic detection on M sliding envelopes in the sequence of discrete digital signals, wherein M is an integer larger than 1. at the antenna unit, receiving one channel of radio frequency signal from a transmitter and N channels of echo signals fed back from a target area, and sending the one channel of radio frequency signal and the N channels of echo signals to the radio frequency unit, wherein N is an integer larger than 1; at the radio frequency unit, equally splitting the one channel of radio frequency signal into N+1 channels of direct signals, demodulating one of the N+1 channels of direct signals to an intermediate frequency signal, sending the intermediate frequency signal to the detection unit, and sending the other N channels of direct signals of the N+1 channels of direct signals that are used as reference signals of the N channels of echo signals respectively and the N channels of echo signals to the data collection unit; at the detection unit, detecting the intermediate frequency signal in a time domain, generating a rising edge trigger signal when detecting a pulse signal in the intermediate frequency signal, amplifying the rising edge trigger signal and sending the amplified rising edge trigger signal to the data collection unit; at the data collection unit, collecting the N channels of direct signals and the N channels of echo signals, upon reception of the rising edge trigger signal from the detection unit, at the detection unit, performing Analog/Digital, A/D, sampling on the intermediate frequency signal in the time domain to obtain a sequence of discrete digital signals; at the detection unit, performing digital signal mixing, low pass filtering, down-sampling and sliding envelope detection on the sequence of discrete digital signals, to obtain a detection result; at the detection unit, comparing the detection result with a preset threshold value, and generating the rising edge trigger signal when the detection result is larger than or equal to the preset threshold value, wherein the sliding envelope detection comprises: at the detection unit, performing periodic detection on M sliding envelopes in the sequence of discrete digital signals, wherein M is an integer larger than 1. at the detection unit, performing periodic detection on M sliding envelopes in the sequence of discrete digital signals, wherein M is an integer larger than 1.