Graphite　carbon　nitride　nanosheets　(g-C3N4　NSs)　are　the　promising　metal-free　polymer-like　semiconductor　nanomaterials,　which　exhibit　excellent　electrochemiluminescence　(ECL)　behavior.　The　g-C3N4　NSs　modified　the　glass　carbon　electrode　showed　the　obvious　ECL　response　using　10 mM　S2O82−　as　the　co-reactant　at　the　scan　rate　of　0.1 V/s.　The　presence　of　Cu2+　would　quench　ECL　emission　due　to　the　photo　induced　electron　transfer　(PET).　Pyrophosphate　anion　(PPi),　an　important　anion　in　several　bioenergetics　and　metabolic　processes,　can　chelate　with　Cu2+　with　a　strong　affinity.　The　introduction　of　PPi　could　release　Cu2+　from　Cu2+-g-C3N4　NSs　system,　resulting　in　the　ECL　recovery.　The　dosage　of　Cu2+　and　the　ECL　recover　time　were　further　investigated.　Under　the　optimized　condition　PPi　can　be　detected　in　the　range　of　2.0–800 nM　with　the　detection　limit　of　75 pM　based　on　3/slope.　This　ECL　sensor　also　possessed　good　selectivity　to　PPi,　and　has　been　used　to　detect　PPi　in　the　synovial　fluid.　©　2016　Elsevier　B.V.