The invention provides a method of selecting a feedback resistor in a superconducting quantum interference sensing assembly. Firstly, a SQUID (superconducting quantum interference device) and a feedback coil are placed in an actual superconducting shielding environment, SQUID magnetic field response periodic characteristics are used, a mutual inductance value between the feedback coil and the SQUID is calculated through monitoring variation of current inputted to the feedback coil, and through monitoring the loaded changed magnetic flux in the superconducting shielding environment and voltage output generated by inputting changed bias current to the SQUID, the corresponding relationship between the outputted voltage value and the sensed magnetic flux and the bias current is built and the mutual inductance value is determined; then, the working process of the assembly in the case of changed magnetic flux, the bias current and feedback resistance is simulated, and on the basis of the corresponding relationship and the mutual inductance value, at least one relationship curve of the SQUID output voltage and the magnetic flux is calculated; and finally, the peak value and the greatest slope in each relationship curve are compared and judged with each preset condition, and matched resistance is determined to be the selected feedback resistance.