To　explore　the　catalytic　activity　of　tungsten　monocarbide　(WC),　the　methane　(CH4)　dehydrogenation　and　further　CC　coupling　process　on　WC　surface　have　been　studied　systematically　by　performing　density　functional　theory　(DFT)　calculations.　The　scaling　relationship　of　the　adsorption　energies　of　CHx　intermediates　on　W-terminated　WC(0001)　surface　has　been　summarized　together　with　those　cases　on　pure　metal　surfaces.　By　the　way,　we　also　studied　the　thermal　stabilities　of　low　Miller　index　surfaces　of　WC　to　obtain　the　Wulff　construction　of　WC　nanocrystal.　The　W-terminated　WC(0001),　W-terminated　WC(112̄1),　and　WC-terminated　WC(112̄0)　facets　constitute　more　than　96%　of　the　total　exposed　surface　in　the　WC　Wulff　construction.　The　van　der　Waals　(vdW)　interaction　between　adsorbate　and　W-terminated　WC(0001)　surface　is　corrected　by　the　BEEF-vdW　functional.　Our　calculations　show　that　W-terminated　WC(0001)　surface　is　the　most　favorably　exposed　surface　with　a　lower　surface　energy.　Based　on　the　data　collected　from　literature,　the　linear　relationship　between　the　CHx　adsorption　energies　and　the　x　in　CHx　on　metal　(e.g.,　Fe,　Co,　Ni,　Cu,　Pt,　Ir,　Rh,　Ru,　Pd,　Ag,　and　Au)　surfaces　has　been　analyzed.　More　interestingly,　we　found　that　the　Co(111),　Ni(111),　and　W-terminated　WC(0001)　surfaces　possess　very　close　slope　factors　in　such　a　linear　relationship,　suggesting　the　similar　catalytic　property　of　methane　dehydrogenation　on　these　surfaces.　More　importantly,　the　rate-limiting　step　of　CH4　dissociation　on　W-terminated　WC(0001)　surface　corresponds　to　CH∗→　C∗+H∗.　The　energy　barrier　[i.e.,　1.46　eV　(1.63　eV)　with　(without)　zero　point　energy　(ZPE)　correction]　for　this　reaction　step　is　slightly　larger　than　the　one　on　Ni(111)　surface　and　smaller　than　the　one　on　Cu(111)　surface.　Furthermore,　we　have　studied　the　CC　coupling　through　the　CH∗　intermediates　on　W-terminated　WC(0001)　surface　and　found　that　the　formation　of　C2H2　is　kinetically　favorable.　Our　results　provides　useful　information　for　the　development　of　tungsten-carbide-based　catalyst　materials.　©　2022　Elsevier　B.V.