In　this　study,　laboratory-scale　experiments　were　conducted　applying　a　Sequencing　Batch　Reactor　(SBR)　activated　sludge　process　to　a　wastewater　stream　from　a　pharmaceutical　factory.　Nitrogen　removal　can　be　achieved　via　partial　nitrification　and　denitrification　and　the　efficiency　was　above　99%　at　23degreesC　+/-　1.　The　experimental　results　indicated　that　the　nitrite　oxidizers　were　more　sensitive　than　ammonia　oxidizers　to　the　free　ammonia　in　the　wastewater.　The　average　accumulation　rate　of　nitrite　was　much　higher　than　that　of　nitrate.　During　nitrogen　removal　via　the　nitrite　pathway,　the　end　of　nitrification　and　denitrification　can　be　exactly　decided　by　monitoring　the　variation　of　pH.　Consequently,　on-line　control　for　nitrogen　removal　from　the　pharmaceutical　manufacturing　wastewater　can　be　achieved　and　the　cost　of　operation　can　be　reduced.