A plant alarm system is one of important safety equipment. Instrument Society of America has proposed an alarm management lifecycle. Although the lifecycle shows guideline of alarm management, business process activities and information exchange between the activities concerned with alarm management are not represented. To perform the alarm management lifecycle, a business process model for alarm management is necessary. In this paper, we propose an alarm management business process model, called AMBPM here after. We have developed the AMBPM based on a business process model for a plant lifecycle engineering. The AMBPM represents business process activities concerned with an alarm management and information exchange between the activities. In a case study, a business flow of an alarm system design process was derived from the AMBPM. The business flow represents specific activities and information for the respective step, whereas the AMBPM represents whole information concerned with the activities.