The creep rules of sandstone are obtained based on the creep test results under different confining pressures. The results show that，Burgers model can effectively describe the instantaneous elastic deformation，attenuation and steady creep deformation of sandstone，and the results fitting at the least square method demonstrate Kelvin model has optimization effect to Burgers model. According to the accelerating creep results under different confining pressures，a modified visco-plastic creep model is obtained by introducing the empirical model and combining Kelvin model for its optimization，and it reflects the accelerated creep characteristics accurately. By combining this modified model with Burgers model in series，a new nonlinear viscoelasto-plastic model can be put forward. Using the 1stOpt software to identify the new model parameters，the results are satisfactory. A comparison between the test and theoretical curves proves the validity of the proposed model.