This article reviews the definitions of digital inclusion from the perspectives of access and use of technology, participation in social activities, assisting vulnerable groups, breakthroughs in social barriers, and reduction of digital divide, and analyzes the relationship between digital exclusion and social inclusion. The influencing factors of digital inclusion are classified into several categories, including ICT acquisition and use, ICT literacy, demographic characteristics, family factors, economic factors, cultural factors, social factors, psychological factors, etc.. Public policy of digital inclusion research is classified into basic telecommunications services, digital training, the effects of digital inclusion policies, and digital inclusion actions in public libraries. The paper reflects on the digital inclusion research and provides suggestions for future research and practice.