Three　polyaniline/graphene　oxide　(PANI/GO)　composites　were　fabricated　by　means　of　an　in-situ　polymerization　of　aniline　monomers　in　the　presence　of　graphene　oxide　(GO).　And　then,　nitrogen-doped　graphene　was　prepared　by　pyrolysis　of　the　PANI/GO　composite.　The　structures　and　morphologies　of　the　samples　were　characterized　by　using　different　techniques,　and　the　electrochemical　performances　of　the　nitrogen-doped　graphene　samples　were　further　investigated.　When　PANI/GO10　(the　GO　feed　content　in　PANI/GO　is　10　wt.%)　was　used　as　a　precursor,　and　the　pyrolysis　temperature　is　800　°C,　nitrogen　content　of　the　as-prepared　nitrogen-doped　graphene　(i.e.,　NG10-800)　is　9.2　at.%.　The　specific　capacitance　of　NG10-800　is　up　to　206　F　g−1　at　a　current　density　of　1　A　g−1,　indicating　an　excellent　electrochemical　performance.　After　1000　cycles　at　a　scan　rate　of　50　mV　s−1,　the　capacitance　retention　of　NG10-800　is　about　92.5%　of　the　initial　value,　suggesting　an　excellent　cycling　stability.　©　2016　Elsevier　B.V.