The present invention relates to a meal service management system and an operating method therefor, the system being capable of providing information on food ingested by a user to whom a meal service is to be provided and customized information related thereto, and managing food leftover in a meal service. According to an embodiment of the present invention, a scanner device is used such that a user to whom a meal service is to be provided and a food tray before and after meals are identified, and thus a meal service amount and a leftovers food amount are acquired, and leftovers food information of each user and useful information associated therewith are provided on the basis of the same, and thus users can easily determine their eating habits, nutritional status and the like and the users can be induced to attempt reducing leftovers food by themselves.