The capacity and stability of constituent electrodes determine the performance of Li-ion batteries. In this study, density functional theory is employed to explore the potential application of recently synthesized two dimensional phosphorene as electrode materials. Our results show that Li atoms can bind strongly with phosphorene monolayer and double layer with significant electron transfer. Besides, the structure of phosphorene is not much influenced by lithiation and the volume change is only 0.2%. A semiconducting to metallic transition is observed after lithiation. The diffusion barrier is calculated to 0.76 and 0.72 eV on monolayer and double layer phosphorene. The theoretical specific capacity of phosphorene monolayer is 432.79 mAh/g, which is larger than other commercial anodes materials. Our findings show that the high capacity, low open circuit voltage, small volume change and electrical conductivity of phosphorene make it a good candidate as electrode material.