In this paper, an ultrahigh sensitive hydrazine electrochemical sensor based on gold nanoparticles integrated into a reduced graphene oxide/nickel foam (AuNPs-rGO@NF) hybrid structure was synthesized using a facile coating and electrochemical deposition method. The morphology and elemental composition of the as-synthesized AuNPs-rGO@NF structure was comprehensively investigated. Both cyclic voltammetry and potential amperometry results show the optimum AuNPs-rGO@NF sensor exhibits excellent electrochemical performances including higher sensitivity (14.635 mu A mu M-1 cm(-2)), lower limit of detection (0.056 mu M; S/N = 3), wider linear detection range (0.2-200 mu M), good selectivity and long-term stability. Meanwhile, the results of real sample analysis indicate the AuNPs-rGO@NF sensor has great potential for practical electrochemical hydrazine sensing applications.