The business process of infrastructure facility maintenance should be integrated correspondingly to the practice of asset management, as well as the maintenance plan should be rationalized more. This study aims to build a methodology of business process reengineering (BPR) for the infrastructure facility maintenance. For this purpose, it firstly investigates the real business process among the maintenance section of a highway corporation and related sections and agents, and secondly describes a series of business process of maintenance by means of unified modeling language, that is, UML, generally available for system description. Lastly it tries to (re) design the business process on the UML model according to the notion of asset management of infrastructure facility.