Abstract: This paper proposes a new analysis method for photovoltaic (PV) modules. The main objectives are to obtain the resistance parameters of PV modules by adjusting I-V equation and voltage equation of diode and to find the relationship between resistance parameters and power. Firstly, values of serial resistance and parallel resistance at maximum power point are concluded. Secondly, the curves of serial resistance and parallel resistance are concluded when load increased from zero to infinity. Thirdly, the relationship between parallel resistance and power is obtained and the influence caused by ignorance of resistances is analyzed. Finally, simulation and experimental results of photovoltaic module show that the method is correct and feasible.