The　characteristics　of　activated　alumina　which　is　taken　as　filter　media　to　remove　phosphorus　and　turbidity　in　drinking　water　were　studied,　and　the　biological　stability　of　effluent　was　analyzed.　When　total　phosphorus　concentration　of　effluent　was　in　range　of　35-45　μg/L　and　turbidity　was　from　3　to　6　NTU,　phosphorus　and　turbidity　removal　efficiency　with　different　granula　size　of　activated　alumina,　L/d10　value,　pH　value　and　filtration　velocity　was　surveyed.　The　result　showed　that　filtration　performance　would　be　worse　with　very　higher　or　lower　value　of　granula　size,　L/d10,　pH　and　higher　filtration　velocity.　Total　phosphorus　removal　efficiency　was　up　to　peak　value　while　granula　size　of　activated　alumina　was　in　range　of　0.71-1.25　mm,　L/d10　1200,　pH　around　6　and　filtration　velocity　was　lower.　On　the　optimal　condition,　the　effluent　could　keep　biological　stability　in　16　hours,　when　the　concentration　of　total　phosphorus　was　less　than　10　μg/L.