In this paper, we explained the layers structure forms an OLED cell and the effect of each layer on light emission process. After studying some circuit models which describe current-voltage behavior of the OLED, we suggested a new simple model with less circuit elements. Due to investigate and examine the accuracy of proposed model we simulated the model using Matlab Simulink and compared it to a reference model. The precision of reference model was proved previously by comparison to experimental data. The comparison between current-voltage characteristic of two models proved the accuracy of the proposed model. Furthermore, using proposed model, we showed that by decreasing resistance of OLED structure layers, its passing current and therefore its emitted light is amplified.