To　enhance　the　production　efficiency　of　short　chain　fatty　acids　(SCFAs)　in　anaerobic　sludge　fermentation　reactor,　sludge　from　another　stabilized　fermentation　reactor　(over　90　days)　under　pH　10　was　seeded　into　the　reactors　to　examine　its　effect　on　SCFAs　production.　Two　sets　of　experiment　were　designed　to　investigate　the　SCFAs　production　with/without　seeding　sludge　under　pH=7.4±0.2　and　pH=10±0.2,　respectively.　Experimental　results　showed　that　(1)　under　same　pH　condition,　the　maximum　SCFAs　accumulation　with　seeding　sludge　additive　increased　by　4.9　mg　COD/g　VSS　(pH=7.4±0.2)　and　16.4　mg　COD/g　VSS　(pH=10±0.2)　respectively,　in　comparison　with　the　control　reactors;　(2)　with　two　reactors　with　seeding　sludge,　the　maximum　SCFAs　accumulation　at　pH　10±0.2　increased　by　146.2　mg　COD/g　VSS　as　compared　with　the　condition　of　pH=7.4±0.2;　(3)　the　maximum　SCFAs　accumulation　at　pH　10±0.2　without　seeding　sludge　was　129.8　mg　COD/g　VSS　higher　than　that　of　pH　7.4±0.2　with　seeding　sludge.　Overall,　seeding　sludge　improved　SCFAs　production　efficiency,　meanwhile,　seeding　sludge　under　alkaline　pH　could　play　synergetic　role　in　enhancing　the　SCFAs　accumulation.　©　2016,　Editorial　Board　of　Journal　of　Harbin　Institute　of　Technology.　All　right　reserved.