The purpose of this study is to identify a suitable organizational diagnostic model for analyzing the management efficiencyof food service firms. We used the three-iteration Delphi technique on a panel of 19 business employees, 7 industry experts,and 4 employees in the food service industry. A total of 36 assessment indicators were developed through this panel, withnumerous major findings. First, it is important to evaluate the leadership qualities of employees in terms of their motivationand competency. Second, it is important to evaluate the ability of employees to interface well with other employees. Third,it is important to evaluate and manage the brand image recognized by customers. Fourth, it is important to evaluate thefairness and regularity of the rewards given for an excellent job performance. Fifth, it is important to evaluate the level ofcommunication and information distribution in the organizational culture. Last, but not least, it is important to evaluate thetransparency and fairness of an organization in its human resource management (HRM) and the efficiency of itsorganizational structure. In conclusion, this study empirically shows how food service firms can develop an organizationaldiagnostic model to increase their managerial efficiency.