Stabilization　of　excess　sewage　sludge　from　antibiotic　production　wastewater　treatment　with　fly　ash　was　studied.　Fly　ash　and　excess　sewage　sludge　were　mixed　in　four　different　ratios　and　three　mixing　times.　Toxicity　characteristics　leaching　procedure　(TCLP),　equilibrium　leaching　test　(ELT),　and　long-term　leaching　test　(LTLT)　were　used　to　investigate　the　teachability　of　heavy　metals.　Taking　heavy　metal　ion　concentration　and　pathogens　into　account,　the　mixture　may　be　qualified　to　be　used　as　soil　conditioner　for　soil　improvement　application.　Surface　complexation　and　deposition　(silicate　and　hydrate　deposition)　were　the　main　mechanisms　of　fixation　of　heavy　metals　by　fly　ash.　Surface　complexation　and　silicate　deposition　worked　in　a　relatively　wider　pH　range,　especially　low　pH.　Hydrate　deposition　worked　at　higher　pH.　It　was　found　that　the　fixing　capacity　increased　with　the　increase　of　the　loading　rate　of　fly　ash.　In　the　study,　fly　ash　can　remove　at　least　92.6%　of　microorganism,　and　the　high　pH　condition　was　considered　to　be　the　predominant　reason　for　killing　pathogens.