By use of the indoor tests and field tests on dynamic characteristics of shear wave velocity, experimental studies on the maximum shear modulus parameters of the foundation soil layers of the earth rockfill dam of a hydropower station have been carried out. The shear wave velocity field tests were conducted by the single hole and cross hole methods, and a total of four groups of the shear modulus with the depth curves were obtained. The curves are consistent with the depth of soil layer and their changes, namely, with the increase in depth, the more dense the soil shear modulus, the overall trend of change. In addition, the volatility of the data also reflects the impacts of the differences on the shear modulus of the soil. The indoor tests on soil consolidation ratio values, density values and impacts given by inhomogeneity of the soil under the wave velocity tests on the results from wave velocity tests and indoor tests are also discussed in this paper. The analysis results indicate that the density values and the inhomeqeneity of the soil are the main influence factors, and the consolidation ration is the secondary. The research results show that the density values of the sample preparation are close to the actual soil layer, and the experiment values are close to the test values obtained from the field.