Four sensing membranes based on fluorescence quenching were prepared by sol-gel method and CA membrane method,and the Ru(Ⅱ) complexes,Ru(bpy)3Cl2 and Ru(phen)3Cl2,were used as the indicators.The results indicate that the volume fraction of oxygen φo2 have a linear relationship in large scale with tanφ0/tanφfor all of the sensing membranes.They have super properties such as excellent limit of detection,fast response time and good reproducibility.The stability of the sensing membranes made by sol-gel method is better than those by CA membranes,but the uniformity of the latter is better than that of the former.