Measurement of the magnetic properties in the field and laboratory analysis were adopted for studying the magnetic variation of the main rocks and soils.andthe relationship between organic carbon and mangetic susceptibity in Guangdongprovinee.the results showed that the magnetic susceptibility of each rock and soil typewas very different,the order of magnetic susceptibility being basalt>granite>quartzite,laterite>lateritic red earth>paddy soil.The magnetic susceptibility showeda significantly positive correlation with the organic carbon of dry land,and asignificantly negative correlation for paddy soil.