The SiO₂sol and anti-reflective coatings were prepared by the acid, base, and acid / base composite catalyzed methods. The surface morphologies of coatings were characterized and their transmissivity and hardness were measured .The experiments results show that, the surface morphology, anti-reflective effect and hardness of the coatings from three sols are very different; The coating from acid-catalyzed sol has the minimum porosity, lowest transmissivity, but highest hardness and best scratch resistance; The coating from ammonia-catalyzed sol gets maximum porosity, highest transmissivity, but lowest hardness and worst scratch resistance; The properties of the coatings from acid / base composite catalyzed sol are between those of the coatings by acid and base catalyzed sol-gel process like porosity, transmissivity, hardness, and scratch resistance performance.These properties will be directly affected by acid / base composite catalyzed sol-gel process.