Geng Xin-HuaMicrostructural,optical and electrical properties of updoped-ZnO films grown by metal organic chemical vapor deposition at different substrate temperature were investigated. XRD spectra and SEM photos indicate that the substrate temperature plays an important role on the microstructure of ZnO films. Morphological transition takes place obviously at around 175℃. The morphology of the ZnO films shows sphere-like structure at low temperature (177℃). The grain size of ZnO films grows up with the increase of substrate temperature. The high mobility (17.96 cm2/Vs) and low resistivity (3.28×10-2Ω·cm) at 177℃ have been obtained for undoped-ZnO film deposited on glass substrate. By further optimizing the structure and B-doping, ZnO film as front electrode will be applied in solar cell soon.