The　effect　of　salinity　on　sludge　alkaline　fermentation　at　low　temperature　(20　degrees　C)　was　investigated,　and　a　kinetic　analysis　was　performed.　Different　doses　of　sodium　chloride　(NaCl,　0-25　g/L)　were　added　into　the　fermentation　system.　The　batch-mode　results　showed　that　the　soluble　chemical　oxygen　demand　(SCOD)　increased　with　salinity.　The　hydrolysate　(soluble　protein,　polysaccharide)　and　the　acidification　products　(short　chain　fatty　acids　(SCFAs),　NH4+-N,　and　PO43--P)　increased　with　salinity　initially,　but　slightly　declined　respectively　at　higher　level　salinity　(20　g/L　or　20-25　g/L).　However,　the　hydrolytic　acidification　performance　increased　in　the　presence　of　salt　compared　to　that　without　salt.　Furthermore,　the　results　of　Haldane　inhibition　kinetics　analysis　showed　that　the　salt　enhanced　the　hydrolysis　rate　of　particulate　organic　matter　from　sludge　particulate　and　the　specific　utilization　of　hydrolysate,　and　decreased　the　specific　utilization　of　SCFAs.　Pearson　correlation　coefficient　analysis　indicated　that　the　importance　of　polysaccharide　on　the　accumulation　of　SCFAs　was　reduced　with　salt　addition,　but　the　importance　of　protein　and　NH4+-N　on　SCFA　accumulation　was　increased.　(C)　2015　The　Research　Center　for　Eco-Environmental　Sciences,　Chinese　Academy　of　Sciences.　Published　by　Elsevier　B.V.