Abstarct: In this experimental research we have synthesized and studied the physical properties of pure and F-doped tin oxide (SnO2) with spray pyrolysis method on glass substrate and then the effect of annealing was investigated. For characterization of synthesized samples we have used various equipment including: Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD) and Hall effect measurements. In the first step, pure tin oxide laxyers were deposited using tin chloride dehydrate (SnCl2.2H2O) in ethanol (Merck) solution in different volumes (20, 50 and 80 ml) (Section 4-2). In the next step, considering the crystallinity and the different preferred orientation in samples prepared with precursor volumes of 20 and 50 ml we investigated the effect of fluorine (F) doping with different weight percentages of 3, 5 and 10. Finally, the effect of annealing on physical properties of pure and fluorine doped samples was studied (sections 4-3 and 4-4). The characterization of the samples showed that all laxyers are in grain forms with different sizes, and from structural point of view all samples are polycrystalline in tetragonal structure. The doping process showed that while the grain sizes are reduced and the electrical resistivity of the laxyers are decreased, their optical band gaps are increased as a result of Brestein-Moss effect. We found sample with the highest doping concentration had the highest figure of merit (1.3×10-2 Ω-1) among other samples. Annealing process (450 ºC in air atmosphere for 1h) in pure and doped samples showed that the grain sizes had an incremental trend, and although in pure samples the band gaps had very little variations, but in doped ones, compared with the as-grown laxyers, it is reduced.