With the rapid development of the western loess region and engineering construction, the time-related practical problems of the loess deformation, strength, and stability in engineering construction are increasing. Time effect or rheology should be considered when solving engineering problems in the loess area. The load and unload creep curves of the Q₃ remolded loess under different confining pressures are obtained through triaxial cyclic loading and unloading rheological tests. Based on the unified rheological mechanical model theory, the three-dimensional rheological constitutive model, namely the improved Nishihara model, which is suitable for the deceleration creep stage of Q₃ remolding loess is identified. In order to describe the accelerated creep stage, the viscosity parameters in a viscoplastic body are written as a function of time, a nonlinear improved Nishihara model is proposed, the corresponding constitutive equation of creep is derived, and the model parameters are obtained by the creep test data. By substituting the model parameters under different confining pressures into the corresponding constitutive equations, the creep curves of the nonlinear improved Nishihara model were compared with the creep test curves. After comparison, it was found that the creep properties of the Q₃ remolded loess could be well reflected by the model.