The organic modified SiO2 sols were prepared by sol-gel method using γ-Methacryloxypropyl trimethoxy silane KH570 as modifier, tetraethylorthosilicate (TEOS) as precursor, and ammonia water as catalyst. Durable antireflective (AR) coatings were then deposited on the glass substrates by dip-coating method. The modified silica AR coatings were characterized by UV-Vis-NIR spectrometry, FTIR, SEM and water contact angle measurement, respectively. The results shown that the modified coating can achieve a high peak transmittance of 99.50% when the molar ratio of KH570 to TEOS was 1:5. After exposed in the humid environment with a relative humidity of 90% for 60 days, the transmittance of SiO2 coating modified by KH570 shown almost no change, which indicate that the environmental stability of the silica coating was greatly improved