Abstract: TiO2 film in various grain size and nano SnO2/TiO2 composite film were prepared by the sol-gel method.Photovoltaic conversion tests were performanced with counter electrode.The results show that the photovoltaic properties will be improved after the film electrodes is sensitized.The small grain films or composite films also has better photovoltaic property.Photovoltaic properti of 25nm TiO2 film sensitized by mercurochrome is 847 times of those of non sensitized 25 nm film.Furthermore,Photovoltaic property of sensitized 25 nm TiO2 film is 5 times of those of sensitized 136 nm film.Photovoltaic property of sensitized 27 nm SnO2/25 nm TiO2 composite film is improved in 7.7%.