Based on the refractive index dispersion effect, the weighted average reflectivity was used as evaluation function, and the best film thickness parameters of the anti-reflection coatings for the space silicon solar cell was obtained by the intelligent optimization algorithm. The optimization results were compared with that of the anti-reflection coatings designed without considering the dispersion. It displayed that after optimizing, the minimal weighted average reflectivity of the MgF2/TiO2 and SiO2/ TiO2 anti-reflection coatings were reduced by 36.6% and 37.6% under considering the dispersion effect than that without considering dispersion effect. And then the MgF2/TiO2 and SiO2/TiO2 anti-reflection coatings were deposited on the silicon solar cells with a thickness of 15 nm SiO2 passivation layer and optimized again. Comparing without considering dispersion effect, the minimal weighted average reflectivity in the case of dispersion was reduced by 43.9% and 33.7% for the MgF2/TiO2 and SiO2/TiO2 coatings with passivation layer, respectively. The optimal design of the anti-reflection coatings were carried out for the space silicon solar cells with different thickness passivation layer. It was found that the minimum weighted average reflectivity of the anti-reflection coatings increased with the increase of the thickness of the passivation layer, meaning that the anti-reflection effect got weaker and weaker. Finally, the anti-reflection coatings were redesigned when the thickness of the passivation layer was also considered as an inversion parameter considering the refractive-index dispersion effect or not. The results show that the anti-reflection film is more optimization by considering the dispersion. For the MgF2/TiO2/SiO2(passivation layer) film system, the optimal film thickness parameters are d1(MgF2)=97.6 nm, d2(TiO2)=40.2 nm, d3(SiO2)=4.9 nm. For the SiO2/TiO2/ SiO2(passivation layer) film system, the optimal film thickness parameters are d1(SiO2)=85.1 nm, d2(TiO2)=43.4 nm, d3(SiO2)=1.8 nm.