Simulated annealing (SA) is a good tool for solving complex nonlinear optimization problem. The development of its parallelism has become the study focus in recent years. An efficient and convergent parallel simulated annealing (PSA) combined with message passing interface (MPI) method is presented for the optimization of diffractive optics elements (DOE). Using an 8CPU parallel computing platform, optimization designs are performed with incident caliber of 310 mm and 20order superGaussian focal spot of 0.4 mm×0.8 mm. The results show that the smoothing effect with the PSA method can be better and the timecost is less than 1/6 than those with serial SA method, which demonstrates the quickness and effectiveness of the PSA.