The effects of SiO2 buffer layer on adhesion and morphology of SiO2 aerogel films deposited on silicon substrate were studied.500nm thick SiO2 film was grown using thermal oxidization method.SiO2 aerogel made by sol-gel method were spining-coated on silicon substrates with and without SiO2 buffer layers.Microscope and SEM images show that the surface morphology of SiO2 aerogel films with SiO2 buffer layer were rough and irregular,while there were lots of gaps and voids on surfaces of sample without SiO2 buffer layer.The phenomenon was attributed to the hydrophilic property difference between Si and SiO2.