The　pilot-and　lab-scale　reactor　was　constructed,　respectively,　to　evaluate　the　influence　of　ammonia　and　nitrite　on　the　performance　of　Fe　and　Mn　removal.　The　results　of　pilot-scale　filter　indicated　that　the　nitrite　concentration　of　0.1,　0.2,　0.3,　0.7　mg/L,　had　no　effects　on　Fe　and　Mn　removal,　as　well　the　ammonia　concentration　of　1.2　and　2.2　mg/L.　However,　the　ammonia　concentration　about　4.5　mg/L　would　inhibit　the　Mn　removal,　resulting　in　higher　Mn　in　effluent　than　requirements;　The　lab-scale　SBR　experiments　demonstrated　that　the　activity　of　Mn　oxidizing　bacteria(MnOB)　was　enhanced　by　nitrite,　but　inhibited　by　ammonia,　which　showed　the　importance　of　nitrification　in　biological　removal　of　Fe,　Mn　and　ammonia　process,　especially　in　the　period　of　start-up.