A　series　of　completely　mixed　anaerobic　reactors　were　operated　to　investigate　different　alkalis　(NaOH　and　Ca　(OH)2)　performance　on　sludge　disintegration　and　organics　hydrolysis　and　acidification　in　sludge　alkaline　fermentation　systems.　In　addition,　ammonia　stripping　was　combined　with　alkali　adjustment　to　observe　the　effect　of　NH4+　concentration　on　the　hydrolysis　and　acidification　effective　of　released　organics.　Results　showed　that　at　pH10,　sludge　disintegration　as　well　as　organics　release,　especially,　volatile　fatty　acids　(VFAs)　was　much　higher　in　NaOH　systems　than　that　in　Ca(OH)　2　systems.　However,　part　of　soluble　protein　and　PO43-　were　precipitated　with　Ca2+　in　Ca(OH)2　systems.　The　PO43-　concentration　was　less　than　40　mg/L　in　Ca(OH)2　systems.　43%　of　NH4+　was　removed　by　ammonia　stripping.　The　maximum　hydrolysis　and　acidification　performance　was　achieved　in　the　NaOH　adjustment　and　ammonia　stripping　system.　The　SCOD,　protein,　carbohydrate　as　well　as　total　VFAs　concentrations　were　6732,　2029,　374　and　2545　mg/L,　respectively,　and　the　NH4+　concentration　was　as　low　as　200　mg/L.　Analysis　results　also　found　that　ammonia　stripping　could　increase　VFAs　production　by　relieving　the　inhibition　of　NH4+　on　acid-forming　bacteria,　and　enhancing　the　fermentation　of　carbohydrate.