The dynamic shear modulus of saturated sandy soils has been analyzed comparatively between laboratory and field tests for 233 samples of the saturated sandy soils.The analysis indicates that the values of the dynamic shear modulus obtained in laboratory are different from those obtained in field;and the deeper the samples are embedded

the more the difference.The dynamic shear modulus and the embedded depth of the soil satisfy the law of a power function

which depends upon its compactness but not significantly on its grain composition.Through real engineering projects

the influence of the maximal dynamic shear modulus from the two kinds of tests on seismic responses has been compared to obtain a statistical empirical formula of the dynamic shear modulus in laboratory and the shear wave velocity in field.The formula is of a certain help for the seismic response analysis of real engineering sites.