Abstract: The performance of the preamplifier circuit of search-coil magnetometer seriously affects the detection accuracy of magnetometer.As the first stage of the magnetometer,the preamplifier must minimize its noise.By analyzing the preamplifier circuit of the French DEMETER satellite and United States THEMIS and MMS satellite,the analysis shown that an ASIC in CMOS technology is able to reach the same levels of performance,in terms of noise and power consumption as the discrete electronics used on space missions.MCM-V technology and ASIC can reduce its volume to a large extent,and meet the requirements of future miniaturized satellite design,and the research and development direction of the preamplifier circuit of the space-borne search-coil magnetometer is put forward.