Using　sodium　carbonate　as　catalyst,　steam　gasification　kinetics　of　four　high　metamorphosed　anthracites　(Vad　=　2.69%-4.35%)　were　investigated　with　isothermal　thermogravimetric　analysis　under　ambient　pressure.　With　and　without　Na2CO3　catalyst,　the　relationships　of　conversion　(x)　with　reaction　time　(t)　for　these　anthracites　were　obtained　within　the　temperature　range　from　750°C　to　950°C　under　reaction　control.　The　shrinkingcore　model　and　modified　volumetric　model　were　used　to　correlate　the　relations　between　x　and　t　for　the　case　with　Na2CO3　as　catalyst.　The　reaction　rate　constants　(k)　at　different　temperatures　were　determined.　The　reaction　activation　energy　(Ea)　and　the　pre-exponential　factor　(k0)　were　predicted　from　the　Arrhenius　equation.　According　to　the　order　of　k　determined　by　the　above　two　models,　the　order　of　activity　of　the　four　anthracites　was　as　follows:　Yong＇an　Fengshai　coal　＞　Yong＇an　Jiashai　coal　＞　Shangjing　coal　＞　Yongding　coal.　Also,　the　Ea,　ranging　from　147.70　kJ·mol-1　to　199.79　kJ·mol-1,　were　estimated　by　this　study.　Comparing　with　the　case　without　catalyst,　the　Ea　and　the　k0　of　the　case　with　Na2CO3　as　catalyst　were　smaller　and　the　catalytic　effect　was　more　obvious　when　the　temperature　was　lower　than　850°C.