Abstract: Based on the comprehensive analysis of the marine and continental depositional environments and distribution characteristics, the comparative experiments are carried out on 311 undisturbed soil samples to study the dynamic shear modulus ratio and damping ratio of Suzhou quaternary sedimentary soil s. The results show that the influences of transgression and soil depth are significantly different for various Suzhou quaternary sedimentary soils on the relationship between shear modulus ratio and shear strain as well as between damping ratio and shear strain. The dynamic shear modulus ratio and damping ratio of marine clay at the depth of 0 ～ 30 m are smaller and larger than those of continental clay at the same elevation, respectively. However, a contrary relationship exists for the marine clay at the depth of 30 ～ 100 m. The depth has a distinct impact on the curves of dynamic shear modulus ratio with shear strain for the marine clay, silt clay, silt sand and continental silt sand as well as on the curves of damping ratio for the marine clay, silt clay and continental silt sand. The fitting parameters and recommended values for the average curves of dynamic shear modulus ratio and damping ratio are given after distinguishing the clay, silt clay, silt and silt sand layers from the depth of 30 m while keeping muddy soil and medium coarse sand as one layer.