The solar panel is power source in the photovoltaic lighting system, and the output characteristic is a significant factor as assessing energy transformation and maximum power point tracking(MPPT)efficiency. In this paper, the module of the solar panel was built by using Matlab/Simulink, and the equivalent circuit of solar panel was also been simulated accurately. On one hand, the output power firstly increased if the voltage grew, and then decreased if the voltage continually grew. On the other hand, the output power could increase when the temperature decreased or when the intensity of illumination increased. In addition, the voltage at the maximum power would decrease if the number of the paralleled solar panels increased, but the tendency would keep the same when the number of the solar panel was bigger than 3. And the maximum output power would increase with the number of the series’ panels increasing. However, the maximum output power would remain unchanged when the number of the panels was more than a certain quantity. This present work can provide theoretical support for building the photovoltaic lighting system.