Porous carbon materials are usually employed as cathode catalysts in Li-O₂ batteries. However, the poor catalytic performance of carbon cathode often results in low capacity and severe overpotential. Herein, we successfully prepared phosphorus doped carbon material by one-step pyrolyzation, effectively improving the performance of Li-O₂ batteries. The discharge capacity of Li-O₂ battery with P doped carbon reaches 3400 m Ah g⁻¹ at 200 mA g⁻¹, which is increased by 52% compared to the un-doped sample. Besides, greatly decreased discharge overpotential and enhanced rate capability are also obtained after phosphorus doping. Furtherly, phosphorus doping was found to crucially affect the growth of discharge products, and the solution driven mechanism becomes more prominent, leading to larger sized discharge products and prolonged battery life. Our work provides a new way of improving the catalytic performance of carbon cathode for Li-O₂ batteries.