Abstract: A reasonable soil constitutive model is one of the key aspects for the land subsidence simulation. Based on the data from layered marks of Shanghai and Changzhou region, the results indicate that the rheology occurs in the sandy soil. In order to investigate the lag phenomena between the deformation in the land subsidence and the variation of the water level of the aquifer, the creep behavior of the saturated sand is studied based on the uniaxial compression tests of undisturbed soils of the 1st, 2nd confined aquifers in Changzhou City. Based on visco-elastic theory, inverse models of creep curves of load tests were set up for Merchant and Burgers model. The analysis results show that the optimum rheological model is Burgers model for different load test curves. The relation between the rheological parameters and applied normal loads were analyzed and discussed.