Abstract: The influence factors of karst development in Xiangcheng section of the passenger dedicated railway from Hangzhou to Changsha was analyzed systematically. By researching on the rule of electrical relative change of different lithology and combining with the cross section of electrical geophysical prospecting, the developed position and developing scale of karst in Xiangcheng section was studied. In the end, based on the engineering drilling data, the accuracy of electrical geophysical prospecting was verified.