The measurement of the electrical conductivity and magnetic permeability of materials has important applications in engineering. In this paper, a long straight cylindrical rod is placed inside the inductor coil of a low-frequency RLC circuit. By analyzing the power of the circuit and the power consumed by the magnetization of the conductor rod, the relationship between the change in the impedance of the inductor coil before and after insertion and the magnetic permeability and electrical conductivity is obtained. After accurately measuring the inductance voltage with a lock-in amplifier, the electrical conductivity and magnetic permeability of the cylindrical rod are calculated using this relationship. Through verification with multiple materials, the correctness of this calculation model is proved, providing a new idea for the rapid measurement of the electromagnetic properties of materials.