In this work, two iterative methods is proposed and described here for solving nonlinear equation of PV cell device. The type of solar cell is single diode model based on its equivalent circuit with various values of load resistance R. These methods do not require second order of derivative and easy to use. The convergence of the proposed method do not discussed here. In order to found the accuracy and efficiency of the proposed and other method, the absolute error value have been calculated and compared. The advantages of the new proposed method can be investigated by comparing with the Improved Hornor-Newton method; and the results obtained indicate that the propose method is more accurate, efficient and easy to use than the second method.