The thin films of SnO2,SnO2:TiO2, SnO2:MoO3, SnO2:WO3, SnO2:Cr2O3, and SnO2: Fe2O3 were prepared by pulsed laser deposition technique using (Nd:YAG) laser of λ = 1064 nm average frequency (6) Hz and pulse duration (10 ns) under vacuum of 10−2 mbar) deposited on glass, n-Si single crystals substrate room temperature with thickness of (100±10) nm. The structures of pure SnO2 and, SnO2:TiO2, SnO2:MoO3, SnO2:WO3, SnO2:Cr2O3, SnO2:Co3O4 compounds were studied by X–ray diffraction the results showed that there was red shift accompanied addition of MoO3 and TiO2 while a blue shift accompanied the addition of WoO3, Cr2O3, Fe2O3 to tin oxide . The gas sensing measurements of NO2 gas showed that SnO2:TiO2 thin films prepared on n- Si substrate have better sensitivity than thin films from the other binary compounds . Maximum sensitivity (231.4%) was obtained from SnO2:TiO2 thin film prepared on n- Si substrate at operating temperature 373K.