PROBLEM TO BE SOLVED: To provide a sterilization algicidal agent composition and a sterilization algicidal method capable of being stored for long time and providing excellent slime control effect, a water treatment agent composition, which is made as one agent, capable of being stored for long time, and providing excellent slime control effect, anticorrosive effect and scale prevention effect, and a water treatment method.SOLUTION: There are provided a sterilization algicidal agent composition containing (A) a brominated sulfamic acid compound and (B) a chlorinated sulfamic acid compound, and having pH of 13 or more, a water treatment agent composition further containing (1) an azole compound in the sterilization algicidal agent composition and having pH of 13 or more, a water treatment agent composition further containing (2) telomer and/or (3) an organic phosphoric acid compound and having pH of 13 or more, and a drainage system and process water system sterilization algicidal method and water treatment method for adding the sterilization algicidal agent composition and these water treatment agent composition.SELECTED DRAWING: NoneCOPYRIGHT: (C)2019,JPO&INPIT【課題】長期保管が可能で、優れたスライムコントロール効果が得られる殺菌殺藻剤組成物及び殺菌殺藻方法、並びに、長期保管が可能で、優れたスライムコントロール効果、防食効果及びスケール防止効果が得られる一剤化された水処理剤組成物及び水処理方法を提供する。【解決手段】（Ａ）臭素化スルファミン酸化合物と（Ｂ）塩素化スルファミン酸化合物を含有する殺菌殺藻剤組成物であって、該組成物のｐＨが１３以上である殺菌殺藻剤組成物、及び該殺菌殺藻剤組成物に更に（１）アゾール化合物を含有し組成物のｐＨが１３以上である水処理剤組成物、また、該水処理剤組成物に更に（２）テロマー及び／又は（３）有機リン酸化合物を含有し組成物のｐＨが１３以上である水処理剤組成物、並びに該殺菌殺藻剤組成物及びこれらの水処理剤組成物を添加する用排水系及び工程水系の殺菌殺藻方法及び水処理方法。【選択図】なし
