A Computerized Emergency Procedure Guideline (EPG) Support System has been developed for BWR and evaluated using training simulator. It aims to enhance the effective utilization of EPG. The system identifies suitable symptom-based operating procedures for present plant status automatically. It has two functions: one is plant status identification function, and the other is man-machine interface function. For the realization of the former function, a method which identifies and prioritize suitable symptom-based operational procedures against present plant status has been developed. As man-machine interface, operation flow chart display has been developed. It express the flow of the identified operating procedures graphically. For easy understanding of the display, important information such as plant status change, priority of operating procedures and completion/uncompletion of the operation is displayed on the operation flow display by different colors.As evaluation test, the response of the system to the design based accidents was evaluated by actual plant operators, using training simulator at BWR Training Center. Through the analysis of interviews and questionnaires to operators, it was shown that the system is effective and can be utilized for a real plant.