The　hydrogen　redox　reactions　are　comprehensively　investigated　as　key　reactions　in　the　electrochemistry　and　hydrogen　production　technology.　However,　the　kinetic　processes　for　hydrogen　redox　reactions　are　not　fully　elucidated.　Herein,　the　kinetics　of　hydrogen　redox　reaction　at　polycrystalline　platinum　disk　electrodes　are　studied　in　acidic　solution　and　the　diffusion-controlled　reaction　mechanisms　are　proposed.　By　analyzing　the　results　obtained　from　cyclic　voltammograms　at　different　scan　rates　at　pH　2.05,　the　diffusion　coefficients　of　H+　and　H2　are　calculated　to　be　(9.7　±　0.9)　×　10−5　and　(6.3　±　0.9)　×　10−5　cm2·s−1　respectively,　which　are　in　good　agreement　with　those　obtained　at　different　values　of　pH,　as　well　as　the　previous　reports.　The　corresponding　kinetic　standard　heterogeneous　rate　constant　(k0)　is　estimated　to　be　6.5　×　10−2　cm·s−1.　This　work　may　be　helpful　and　universal　to　understand　electrochemical　reaction　kinetic　questions　and　can　be　extended　to　other　similar　systems　for　development　of　highly　efficient　catalysts　toward　hydrogen　redox　reactions.　©　2022　Elsevier　B.V.