Vaccine hesitation refers to the refusal or delay of vaccination when vaccination services are available and is one of the top ten threats to global health. Vaccine hesitation varies in different countries,and its influencing factors are very complex.However,domestic research on this phenomenon is still in its infancy.This article reviews the phenomenon of vaccine hesitation,the occurrence and influencing factors of vaccine hesitation in some developed countries since the 21st century,to provide the basis for taking effective measures for the phenomenon of vaccine hesitation in China.