Nitrogen-doped graphene deposited on nickel foam was prepared via a simple hydrothermal process using urea as the reducing agent and nitrogen source and was directly applied as a binder-free supercapacitor electrode. The N content was 5.01 at. %. The electrochemical test of the prepared N-doped graphene showed ideal and reversible capacitive behaviour and excellent electrochemical performance, with a high specific capacitance of 223 F g(-1) at 0.29 A g(-1), a high-rate capability with the specific capacitances maintained at 184 F g(-1) at a high rate of 35.7 A g(-1), and good cycling stability with the specific capacitance of the N-doped graphene increased to 206 F g(-1) after 3000 cycles. The results suggest its promising application as an electrode material for supercapacitor.