This chapter investigates the purposes of social media use among older adults in China and the factors associated with these behaviors, drawing on data from the 2020 China Longitudinal Aging Social Survey (CLASS). Among the 2,805 respondents aged 65 years or older who regularly used social media, the most common purposes were chatting with family and friends (93.1%), reading news (72.1%), entertainment (63.2%), and seeking general information (44.4%). Less common were online shopping, travel, and health management. Multivariable logistic regression analyses reveal that age, gender, education, occupation, marital status, social networks, leisure activity, health conditions, and regional residence all significantly shape purpose-specific engagement. For example, men are more likely to seek news and information, while women prioritize communication and entertainment. Socioeconomic status, particularly education, plays a pivotal role, often modifying urban-rural differences. These findings underscore the multifaceted and stratified nature of digital engagement in later life and have implications for policy interventions aimed at promoting digital inclusion and healthy aging in China’s rapidly aging society.