Zinc tin oxide(ZTO) thin films, with zinc acetate and tributyltin chloride as raw materials, were deposited on glass substrates by the method of metal organic chemical vapor deposition(MOCVD). The crystallization, microstructure and optical properties were investigated by scanning electronic microscope(SEM),X-ray diffraction(XRD) and ultraviolet-visible(UV-Vis)spectrophotometer. The results show that with the increase in Sn/Zn ratio, the crystal changes from wurtzite to rutile phase. When the ratio reaches 11:18,the intensity of Zn_2SnO_4 peaks appears to be the strongest and the optical band gap is about 3.27 eV. Calculated by the envelope method, the thickness of the ZTO thin films is 713.24 nm.Measured by UV-Vis spectrophotometer, the transmittance of the ZTO thin films reaches up to 80% in the wavelength range of 400-1000 nm when the Sn/Zn ratio is 7:18. Zinc tin oxide (ZTO) thin films, with zinc acetate and tributyltin chloride as raw materials, were deposited on glass substrates by the method of metal organic chemical vapor deposition (MOCVD). The crystallization, microstructure and optical properties were investigated by scanning electronic microscope (SEM), X-ray diffraction (XRD) and ultraviolet-visible (UV-Vis) spectrophotometer. The results show that with the increase in Sn / Zn ratio, the crystal changes from wurtzite to rutile phase. When the ratio reaches 11: 18, the intensity of Zn_2SnO_4 peaks appears to be the strongest and the optical band gap is about 3.27 eV. Calculated by the envelope method, the thickness of the ZTO thin films is 713.24 nm. Measured by UV-Vis spectrophotometer, transmittance of the ZTO thin films reach up to 80% in the wavelength range of 400-1000 nm when the Sn / Zn ratio is 7:18.