According to the experimental data of K9 glass, ZnS crystal, MgF₂ crystal and calcite crystal, the dispersion equations of the materials was established by the application of genetic simulated annealing algorithm to retrieval parameter of the modified sellmeier equation. Meanwhile, the differences in iteration searching properties between the genetic simulated annealing algorithm and the genetic algorithms including standard genetic algorithm and multi-population genetic algorithm were compared. The results show that the genetic simulated annealing algorithm possesses the best optimization effect and stable performance. Finally, the dispersion equations of K9 glass and crystals obtained by genetic simulated annealing algorithm in one spectral region are used in another spectral region, and the fitted values of dispersion equation are in good agreement with experimental data, indicating that the dispersion equation has better extrapolation. Therefore, retrieval parameter of dispersion equation using genetic simulated annealing algorithm can be applied to other materials.