A　numerical　model　on　methane/air　combustion　inside　a　small　Swiss-roll　combustor　was　set　up　to　investigate　the　flame　position　of　small-scale　combustion.　The　simulation　results　show　that　the　combustion　flame　could　be　maintained　in　the　central　area　of　the　combustor　only　when　the　speed　and　equivalence　ratio　are　all　within　a　narrow　and　specific　range.　For　high　inlet　velocity,　the　combustion　could　be　sustained　stably　even　with　a　very　lean　fuel　and　the　flame　always　stayed　at　the　first　corner　of　reactant　channel　because　of　the　strong　convection　heat　transfer　and　preheating.　For　low　inlet　velocity,　small　amounts　of　fuel　could　combust　stably　in　the　central　area　of　the　combustor,　because　heat　was　appropriately　transferred　from　the　gas　to　the　inlet　mixture.　Whereas,　for　the　low　premixed　gas　flow,　only　in　certain　conditions　(Φ　=　0.8~1.2　when　v0　=　1.0　m/s,　Φ　=　1.0　when　v0　=　0.5　m/s)　the　small-scale　combustion　could　be　maintained.