Using Service-Oriented Architecture (SOA) to build an information system is a hot topic at present. The primary goal of this paper is to investigate how to build a SOA-based information system in a special industry-the field of emergency vehicles in environment protection industry. The paper provides a presentation of current compositions of the emergency vehicles information system and then gives out the system structure. The paper proceeds with the business process flow and working principle of an emergency vehicle information system. A service-oriented architecture framework for emergency vehicles information system is proposed.