In this paper, the monodisperse nano-SiO2 particles were obtained via a novel improved stober method, and the micro-meso porous SiO2 xerogels was further obtained after drying in air. The nano-SiO2 particles with the average size of 20 nm, exhibited good dispersibility in alcohol.The as-obtained amorphous SiO2 xerogels were featured with Si-OH and Si-OR groups on the surface, implying a imcomplete hydrolysis and condensation process. Meanwhile, a large number of defects were remained inside and on the surface of the SiO2 xerogels, thus displaying good photoluminescence behaviors. The ultraviolet (λem = 355 nm) fluorescence under λex = 300 nm excitation as well as the visible light (λem = 430nm) phosphorescent under λex = 380nm excitation was observed in the as-obtained SiO2 xerogels. The calculated results according to N2 sorption isotherms demonstrated that specific surface area of the SiO2 xerogels was 559 m2 /g, the pore volume was 0.62 cc/g and a large number of micropores and mesopores were existed in the SiO2 xerogels.