Recently construction industry has been changed highly, widely, complexly and multi-functionally. This change has brought construction industry a new paradigm. This new paradigm and uniqueness of construction industry increase disaster occurrences during construction. Safety management, therefore, has focused on the disaster occurrences. Especially among safety management, safety management of temporary facilities is very important. When temporary facilities are fallen down into disasters, they will bring fatal accidents. Therefore, the purpose of this study is to suggest efficient safety management for the prevention of disasters of formwork for RC construction through the mechanism analysis of disasters. This paper was validated by applying the mechanism eventually to the case of disasters of temporary facilities.