The　biodegradation　of　benz　[alpha]　anthracene　(BaA),　a　high　molecular　weight　polycyclic　aromatic　hydrocarbons　(PAH)　was　increased　via　a　combination　of　alkyl　polyglucosides　and　alkaline　treatment　during　the　waste　activated　sludge　(WAS)　anaerobic　fermentation.　During　the　experimental　study,　the　biodegradation　efficiency　of　BaA　was　enhanced　from　12.2%　in　the　control　to　25.6%　at　pH　10　and　46.7%　at　pH　10　and　alkyl　polyglucosides　(APG)　reactors.　APG　and　alkaline　treatment　increased　the　BaA　deposition　desorption　from　the　sludge　and　transfer　into　micro-organisms　and　finally　increased　the　BaA　bioavailability.　In　the　meantime,　the　enormous　secretion　of　substrates　from　the　WAS　not　only　served　as　carbon　source　but　was　also　engaged　in　the　electron　transfer　among　the　micro-organisms　which　take　part　in　the　BaA　biodegradation　process.　Therefore,　the　microbial　activity　also　engaged　in　the　biodegradation　of　BaA　like　genes　quantity,　the　activity　of　enzymes　and　functional　of　bacteria,　were　also　increased　due　to　the　APG　and　alkaline　treatments.　Overall,　the　instantaneous　enhancement　of　microbial　activity　and　BaA　bioavailability　increased　biodegradation　efficiency.