The food safety problem of on-line take-out food enterprises is a hot issue of current research. This paper chooses two typical on-line take-out food enterprises in J City as the research object, and uses the mathematical statistics, logical reasoning and model evaluation methods to conduct in-depth research on the food safety of on-line take-out food service enterprises. The main results are as follows: (i) The rapid growth of on-line take-out food service industry poses a serious challenge to food safety in today's society; (ii) This paper constructs an food safety evaluation index system for the on-line take-out food service enterprises, which includes four modules (management qualification; procurement and transportation; conversion of finished products; take-out delivery), and 17 specific evaluation indexes, such as catering licensing status, health status of employees and management system; (iii) Using the evaluation index system in (ii), this paper evaluates the food safety status of enterprises A and B in J City, and finds that the two enterprises have different levels of food safety problems, which are mainly reflected in two modules: procurement and transportation; take-out delivery.