The　search　for　a　biocompatible　co-reactant　for　tris(2,2＇-bipyridine)ruthenium(II)　(Ru(bpy)(3)(2+))　electrochemiluminescence　(ECL)　has　attracted　broad　attention　towards　extending　its　application　in　the　biomedical　field.　This　work　investigates　the　co-reactant　effect　of　graphitic　carbon　nitride　nanosheets　(CNNSs)　on　Ru(bpy)(3)(2+)　ECL.　CNNSs　enhance　the　anodic　ECL　of　Ru(bpy)(3)(2+)　through　the　ECL　interaction　between　Ru(bpy)(3)(3+)　and　the　reductive　intermediate　of　CNNSs,　which　are　generated　by　either　the　direct　electroreduction　of　CNNSs　or　the　chemical/electrochemical　oxidation　of　the　amine　groups　on　the　CNNSs　surface　by　Ru(bpy)(3)(3+).　The　finding　may　provide　a　new　avenue　for　the　development　of　self-enhanced　ECL　probes　and　offer　a　new　insight　into　revealing　the　surface　feature　of　CNNSs.