Abstract： Objective To evaluate construction and implementation of the Shandong Monitoring Platform for Vaccine Cold Chain.Methods We constructed a monitoring platform for vaccine cold chain management covering all-level centers for disease control and prevention(CDC)and all vaccination units in Shandong using advanced technologies of 5G,Big Data,Internet of Things,and 5G-based temperature and humidity recording devices for data collection.We evaluated the running effectiveness of the platform in 2023.Results The platform covers the provincial CDC,16 prefectural CDCs,152 county-level CDCs,and 4 202 vaccination units in Shandong equipped with 5 313 5G-based temperature and humidity recorders.The core functions of the platform include real-time temperature monitoring of cold chain equipment,abnormity alarming,and evaluation of management quality.The temperature stability values of an ordinary cold room ranged from 0.33 to 0.56,indicating good stability.The overall average monthly abnormal temperature alarms per equipment was 1.4,with 0.6,1.4,1.7,and 1.4 for the provincial CDC,prefectural CDCs,county-level CDCs,and vaccination units,respectively.Rates for complete cold chain equipment archives,timely data upload,Cold Chain Cloud registration,complete unit audit,and timely alarm disposal were 99.98％-100％,99.45％-100％,98.11％-100％,98.33％-100％,and 89.70％-100％.Conclusions The Shandong Monitoring Platform for Vaccine Cold Chain accomplishes end-to-end temperature monitoring in vaccine storage and transportation,improves vaccine cold chain management,and helps ensure vaccine safety and effectiveness.