Abstract: In oue research,SnO2 thin film on glass fibers has been fabricated using ethanol as solvent and pent hydrate tin chloride as staring material by Sol-gel method.A thin film with different thicknesses on glass fibers has been obtained by choosing different concentrations of the reactant and dipping times.The effect of the film thickness on the structure,transmittance of the thin film and the resistivity of glass fibers have been investigated.The results show that with the rising of the film thickness,the degree of crystallinity of the film,the grain size and the conductive performancewill increase,while the light transmission rate gradually decreases.When the thickness of the thin film is 557 nm,the resistivity will be the smallest,which is 0.16 Ω·m.The transmittance will exceed to 76% when the thickness of the thin film increases from 56 nm to 340 nm.With further increasing of the thickness,the transmittance will decrease to less than 62%.