Abstract： Objective To assess wastage rates of National Immunization Program(NIP)vaccines in China.Methods We selected 400 vaccination units from 21 counties/districts of 8 provinces in eastern,central,and western regions of China and obtained data on consumed and administered doses of 4 multi-dose-vial vaccines and 7 single-dose-vial vaccines in 2022 to determine wastage coefficients,reasons for wastage,and influencing factors.Results The overall wastage coefficient of all NIP vaccines was 1.25 in the surveyed vaccination units and was 2.04(range:1.52-3.30)for multi-dose-vial vaccines and 1.02(range:1.00-1.06)for single-dose-vial vaccines.Linear regression analysis showed that vaccination unit level,service frequency,specific vaccination service for multi-dose-vial vaccines,daily doses administered,and number of vaccinators were factors influencing vaccine wastage.Wastage from exceeding the time limit of opened vials accounted for 97.54％of all wastage of opened vaccine vials and the wastage from exceeding expiration dates accounted for 69.15％of all wastage of unopened vaccine vials.Conclusions Wastage coefficients of multi-dose-vial vaccines were much higher than those of single-dose-vial vaccines.We suggest optimizing the packaging of multi-dose-vial vaccines and vaccination service modes and strengthening vaccine planning to improve the efficiency of vaccine use.