Abstract In this study, the irradiation coloring effects by 60 keV protons on space applied lens coated with a MgF 2/ZrO 2/Al 2O 3 optical multilayer antireflection film were investigated by ground experiment and computer simulation methods. The energy loss within each layer of the antireflection film caused by proton irradiation was calculated using SRIM program based on the Monte Carlo simulation approach. It was shown that the lower energy proton irradiation led to a smaller range, but induced larger energy loss, resulting in worse damage in the antireflection film. Degradation in spectrum transmission of the lens irradiated by 60 keV protons using a synthesized space irradiation simulation facility was examined. Evolutions of the color centers in the irradiated films were also evaluated by absorption spectrometry techniques. It was found that the F 2 color centers in the MgF 2 film, and the V ŌH and F 2+ color centers in the Al 2O 3 film are responsible for the absorption bands at 370 nm, 400 nm and 440–450 nm, respectively. The absorption band at 490 nm was caused by F+ color centers in the ZrO 2 film, and the absorption band at 580–660 nm was induced by some impurity color centers.