Abstarct: In this thesis,nano strutures Sno2,Tio2 and core-shell Sno2-Tio2 with molar percentage 1:1,1:1/5,1:2prepared by sol-gel method. Then,properties structural and optical and as well as their sensing efficiency in presence of gases ethanol and acetone investigated. In order to check the properties structural of the samples,measurements X-ray diffraction XRD and microscopy field effect electron used. There sults of examining the patterns XRD sampies Ts1,Ts2,Ts3 the formation of the structure of four anatase titanium oxide and the four structure of castrite tin oxide confirmed the study of the properties optical of the samples showed that the band gaf of the samples with the increase of the thichness in creases. Images the FESEM of the samples show are morphology almost the same and porosity different the results of the performance testing samples Ts1,Ts2,Ts3 against gases showed that Ts1,Ts2,Ts3 at a temperature of 250°C respectirely showed sensitivity better.