Under the present situation of severe competition in the food industry, food industry should put much emphasis on maintaing repeating guests as well as attracting new guests. Food industry should gain competition superiority with relationship marketing which consists of the interaction between the role of guests as participants and the guests-oriented service of employees, and marketing activities building up, maintaining, and enforcing the relationship with the guests. However, food industry in Korea have not had much interests in the relationship marketing Which can maintain repeating guests, and they have not carried out relationship marketing activities. This study attempted to establish the relationship marketing strategy of the food industry for the maintenance of friendly relationship with its guests. After reviewing the precedent theory of relationship marketing, the study tried to find out the important factors to affect the relationship marketing of food industry.