The invention discloses an S-band multi-channel high-precision space ranging transponder. The S-band multi-channel high-precision space ranging transponder comprises a power supply, a command module,a receiving channel, a digital baseband, a transmission channel, an interface module, and a self-calibration module, wherein the receiving channel is used for receiving an uplink radio-frequency signal and performing low noise amplification, down conversion, intermediate frequency filtering, intermediate frequency signal amplification, and AGC telemetry control; the digital baseband is used for sampling and outputting calculated PCM telemetry code, synchronous clock, and strobe pulse after acquisition and tracking of a spreading code, acquisition and tracking of a carrier wave, and remote control information bit synchronization are conducted on the uplink telemetry channel; the PCM telemetry code is subjected to spectrum spreading and BPSK modulation in a downlink telemetry channel, and amodulated downlink spread spectrum signal is outputted; a range zero value of a transponder is calculated; the transmission channel is used for performing uplink frequency conversion, radio frequencyfiltering, and power amplification, and then a radio frequency signal is obtained and transmitted; the interface module is used for interacting with an on-board computer for satellite telemetry data,transponder telemetry data, and satellite remote control data; and the self-calibration module calculates the range zero value of the self-calibration module according to the digital baseband for self-calibration. The S-band multi-channel high-precision space ranging transponder has the advantages that the function is complete, ranging precision is high, and the structure is simple.