An expert system for stroke diagnosis was designed in this study. The causes of stroke in the central nervous systems are very diverse, symptoms may not appear in the early stage, so diagnosis ran be difficult. Also, doctors who treats patients with stroke must have expert knowledge for the quick and correct impending diagnosis. Therefore, an expert system for assisting the impending diagnosis of stroke has needed to be developed. In addition, the diagnosis system can be used as an simulator for medical students who study neurology. In this study, and diagnosis expert system was developed. It serves a pathological data bus provided by an interface. An inference engine makes an impending diagnosis of stroke possible. We implemented the system using Windows2000 Server, IIS5.0 and ASP.