Short-chain　fatty　acids　(SCFAs)　recovery　through　anaerobic　fermentation　is　a　promising　pathway　to　achieve　economic　benefits　and　carbon-emission　reduction　in　waste　activated　sludge　management.　Although　numerous　pretreatment　approaches　have　been　investigated,　alkaline　hydrolase　blend　(AHB)　incubation　at　initial　pH　10.0　condition　for　enhancing　anaerobic　fermentation　has　rarely　been　reported.　In　this　study,　the　sludge　flocs　were　disintegrated　into　electronegative　particle　fragments　with　extracellular　polymeric　substance　disruption　and　microbial　cell　lysis,　owing　to　the　synergistic　effect　of　alkali-triggered　sludge　solubilization　and　AHB-catalyzed　hydrolysis.　Substantial　sludge　hydrolysis　and　biodegradable　organic　matter　release　were　thereby　induced.　After　pH　10　+　AHB　pretreatment　for　2　h,　numerous　SCOD　release　of　5109　mg/L　was　achievable,　which　was　approximately　12.4,　2.02,　and　1.19　times　higher　than　those　in　control,　pH　10　and　pH　10+alkaline　protease　pretreatments,　respectively.　Meanwhile,　the　AHB　boosted　hydrolysis　and　biodegradation　of　dissolved　organic　matters,　promoting　a　low　molecular　weight　shift　in　molecular　weight　distribution.　The　dissolved　organic　matter　compositions　tended　to　low　molecular　weight　organic　matters,　accelerating　the　overall　anaerobic　fermentation　process.　Correspondingly,　considerable　SCFAs　of　528.9　mg　COD/g　VSS　was　produced　through　a　short-term　anaerobic　fermentation　(3　days),　which　was　5.6,　1.7　and　1.1　times　higher　than　the　maximum　SCFAs　production　by　control,　pH　10　and　pH　12–10+alkaline　protease　pretreatments,　respectively.　The　produced　SCFAs　were　mostly　composed　of　acetate　(58.7%),　which　could　be　recovered　as　biodegradable　carbon　source.　By　adopting　the　AHB-based　strategy,　economic　benefits　of　392.4–580.6　CNY/ton　sludge　SS　and　carbon-emission　reduction　of　0.207–0.521　ton　CO2/ton　sludge　SS　were　achievable.　Apparently,　the　AHB-based　strategy　is　a　cost-effective　and　carbon-beneficial　technology　for　sludge　management.　©　2022　Elsevier　Ltd