The　pre-denitrification　SBR　process　of　treating　municipal　waste　water　including　phenol　was　investigated　with　the　combination　of　short-term　and　long-term　tests.　The　results　show　that　the　ammonia　oxidation　rate　decreases　gradually　with　the　increase　of　concentration　of　phenol　(0-175　mg/L),　with　the　specific　substrate　ulitization　rates　ranging　of　2.898-0.694　d-1.　The　average　ammonia　oxidation　rate　is　4.091　mg/(g·h)　in　pre-denitrification　system　and　2.26　times　short-term　test　result　(1.812　mg/(g·h)).　The　ratio　of　ammonia　oxidation　rate　to　phenol　concerntration　keeps　at　-0.031±0.005.　The　phenol　and　ammonia　can　be　removed　at　0-5　h　with　the　respective　removal　efficiencies　of　24.2%　and　23.5%.　Moreover,　the　ammonia　oxidation　damage　can　be　recovered　to　normal　levels　after　15-18　d　through　microbial　own　structure　function　change.　However,　the　toxicity　inhibition　at　the　high　phenol　concentrations　exhibites　an　irreversible　damage,　and　DNA　concentration　in　extracellular　polymer　substance　varies　from　2.53　mg/g　up　to　34.6　mg/g.