Abstract: The steady state Rayleigh wave method with the electromagnetic seismic source, as an earliest applied surface wave exploration method, has been applied near ten years since in China. In recent ten years, based on both theoretical and test studies, the obvious progresses in the data acquisition, processing and interpretation were obtained; it is determined that the "flex point" and "zigzag" anomalies are two basic abnormal forms of stratigraphic boundaries on the D-_vR curves; based on the form of single curve, the basic types of geological anomalies such as cave, fracture, loose belt and so on are determined; and the measured data from the depth more than one or two hundred meters are obtained. This method has been successfully applied in the engineering projects of larger, medium and smaller types, and some complex engineering geologic problems were solved. The higher levels in the exploration depth, interpretation accuracy and cave diagnosis accuracy are attained. On these aspects, the advantages of steady state method are difficultly comparable by other similar geophysical methods including the present transient surface wave method. It can be predicted that both exploration level of Rayleigh wave and the capacity of solving various complex geologic problems would be further increased with the development of both steady state method and transient method as well as instrument.