Objective To analyze the connotation of the third-party platform liability system for online food transactions, discuss the existing problems of the system, and provide reasonable suggestions for improving the third-party platform liability system for online food transactions. Methods The obligations and responsibilities of the third party platform were clarified by the relevant legal provisions. The importance of fulfilling the obligations of third-party platforms is illustrated by case analysis. Combining with practice, this paper explores the problems existing in the third-party platform of online food transaction. Results There are some problems in the liability system of the third-party platform of online food transaction, such as unclear legal provisions, ineffective information sharing, lack of internal motivation to implement the review obligation, and unclear responsibility boundaries. Conclusion There are still many problems in the responsibility system of the third-party platform of online food. It is necessary to perfect laws and regulations, build prevention system and reward reporting system, establish information sharing system, and establish responsibility sharing and co-governance mechanism.