Objective: To analyze the basic policy texts of centralized procurement of non-immunization program vaccines, reveal the main procedures and core elements of vaccine procurement, and propose optimization suggestions. Methods: The content analysis method is used to conduct word frequency statistics and co-occurrence network construction. Combined with the comparative analysis method, the commonalities and differences in the procurement of non-immunization program vaccines in different regions are summarized. Results: The centralized procurement procedures for non-immunization program vaccines include planning, selection and implement. It involves 17 core elements including procurement catalogs, vaccine announcement, and vaccine reception. Among them, the centralized procurement cycle is mainly 1 year, and most vaccine quotation is based on reference of the surrounding provinces, the evaluation is mainly on expert review. Conclusion: The centralized procurement procedures and frameworks of the non-immunization program vaccines are consistent, and the procurement environment tends to be open and standardized. The monitoring and evaluation of the non-immunization program vaccines should be improved, the selection criteria should be deepened, and the evaluation talent team should be improved to promote the healthy development of the vaccine procurement.