The magnetic susceptibility and its relationship with the total content, DTPA extractable content and activity index of heavy metals of urban soils in Nanjing city were studied. The results showed that the magnetic susceptibility of urban soil was higher, and the frequency-dependent susceptibility was lower as compared with those of natural soil. The measurement of magnetic susceptibility provided a simple, quick means for monitoring the pollution status of Cu, Zn, Pb in urban soils.