A silica glass optical material for projection lens to be used in vacuum ultraviolet radiation lithography using radiation from 155 to 195 nm in wavelength, wherein, said silica glass optical material is of ultrahigh purity, contains from 1 to 10 wtppm of OH groups, from 100 to 10,000 wtppm of F, and from 1.times.10.sup.17 to 1.times.10.sup.19 molecules/cm.sup.3 of H.sub.2, and has a distribution in concentration of F that is axially symmetrical to the central axis.