Nanodispersion of zirconium dioxide was made via sol-gel process, using zirconium (IV) n-propoxide (Zr(OPr)4). After adding organic component, the hybrid dispersion was coated on substrate (BK7) by spin-coating and dried. The transmittance of the thin film on BK7 was determined by using optical spectrophotometer, over wavelength range of 350 through 1000 nm. Then the reflective index and film thickness can be determined by using an “envelope method”[1]. High refractive index were observed in certain composition 1. Manifacier, J.C., Gasiot, J., Fillard, J.P. J.Phys. E (1976) 9:1002-1004