Background:　Measurement　of　endogenous　cellular　hydrogen　peroxide　(H2O2)　2　O　2　)　can　provide　information　on　cellular　status,　and　help　to　understand　cellular　metabolism　and　signaling　processes,　thus　contributing　to　elucidation　of　disease　mechanisms　and　new　diagnostics/therapeutic　approaches.　Results:　In　this　work,　Pt-Cd　bimetallic　nanozyme　was　successfully　prepared　via　the　solvothermal　synthetic　method　for　sensitive　detection　of　H2O2.　2　O　2　.　The　synthesized　Pt-Cd　bimetallic　nanozyme　could　exhibited　good　electrochemical　activity.　Then,　the　materials　were　analyzed　for　the　electrochemical　properties　and　catalytic　properties　of　H2O2　2　O　2　by　cyclic　voltammetry　and　chronoamperometry,　respectively.　Results　indicated　that　the　synthesized　nanozyme　had　superior　sensitivity　(295　mu　A　mM-　1　cm-　2　)　and　selectivity　toward　H2O2　2　O　2　with　a　detection　limit　of　0.21　mu　M.　Further,　the　Pt-Cd　bimetallic　nanozyme　displayed　good　electrochemical　properties　compared　to　platinum　catalysts　alone.　The　application　was　extended　to　determine　the　produced　H2O2　2　O　2　from　human　hepatocellular　carcinoma　cells　(HepG2)　and　normal　hepatocyte　(LO2)　samples　after　ascorbic　acid　stimulation,　thus　enabling　the　early　warning　of　cellular　carcinogenesis.　Significance:　This　strategy　promises　simple,　rapid,　inexpensive　and　effective　electrochemical　sensing　and　provides　a　new　pathway　for　the　synthesis　of　bimetallic　nanozymes　to　construct　an　electrochemical　sensor　for　the　sensitive　detection　of　H2O2.　2　O　2　.