Fire engine design is based on the traditional method and product design cycle. In this way, it cost a lot of time. The article proposed a new fire engine design flow. Under the parameter restraint conceptual design method, Rapid Design System (QDS) constructed the database which has the parameter reference value non-parameter model. This article taken the fire engine as an example, and constructed the fire engine Rapid Design System using Script, Visual Basic 2008, and Access2007. The example confirmed this method to raise fire engine's design efficiency.