In　order　to　achieve　fuzzy　control　of　denitrification　in　a　Sequencing　Batch　Reactor　(SBR)　brewery　wastewater　was　used　as　the　substrate.　The　effects　of　brewery　wastewater,　sodium　acetate,　methanol　and　endogenous　carbon　source　on　the　relationships　between　pH,　ORP　and　denitrification　were　investigated.　Also　different　quantities　of　brewery　wastewater　were　examined.　All　the　results　indicated　that　the　nitrate　apex　and　nitrate　knee　occurred　in　the　pH　and　ORP　profiles　at　the　end　of　denitrification.　And　when　carbon　was　the　limiting　factor,　through　comparing　the　different　increasing　rate　of　pH　whether　the　carbon　was　enough　or　not　could　be　known,　and　when　the　carbon　should　be　added　again　could　be　decided.　On　the　basis　of　this,　the　fuzzy　controller　for　denitrification　in　SBR　was　constructed,　and　the　on-line　fuzzy　control　experiments　comparing　three　methods　of　carbon　addition　were　carried　out.　The　results　showed　that　continuous　carbon　addition　at　a　low　rate　might　be　the　best　method,　it　could　not　only　give　higher　denitrification　rate　but　also　reduce　the　re-aeration　time　as　much　as　possible.　It　appears　promising　to　use　pH　and　ORP　as　fuzzy　control　parameters　to　control　the　denitrification　time　and　the　addition　of　carbon.