A viscoplastic finite element method for simulating powder sintering processes was presented. This method was formulated on the basis of the plasticity theory of a porous material to take the change in apparent volume during the sintering into consideration. To simulate non-uniform shrinkage in the sintering, the shrinkage strain-rate was included in the formulation. In addition, both microscopic and macroscopic shrinkages in the sintering were simulated by coupling the finite element method with the Monte Carlo method. The calculated results in sintering processes were shown.