A computer expert system for guiding Japanese style meal menu has been developed by using EXSYS Professional which is one of expert system developing software tools. The expert system nunderstands the situations of clients, and can guide the menu as human experts do by its software program with expert knowledge about the meal menu. In developing the expert system, the elements the clients consider when selecting menu were arranged as questions of the expert system, and the final outcome of the expert system resulted in selecting the final menu appropriate for the client demand, weather, health, etc. In hotel, the expert system can be shared by whole restaurants, and be directly a computer guider to the clients to tell the best choice of the menu. Besides, it can be used for various kinds of bangquets and events. Expert system has been developed and studied by business managers, manufactures, medical fields, and military field. But the studies for applying the expert system in the fields of foods have been scare. Through this study, therefore, the expert system is going to be applied more widely in many fields fo food events.