A sort of one axle tracking Solar Photovoltaic system is presented. To solve the problem of low conversion efficiency in existing systems, the method of timing light intensity comparison is proposed to achieve automatic tracking of solar cells. Based on this, combining practical applications at present, the way of using one axle tracking can improve the Photo-electricity Changing Efficiency. Furthermore, the method of the one axle tracking is simple and firm at structure, it does not reduce the system’s resisting wind capability, so that it has better practicability and value to extend.