Based on the questionnaire data of 300 elderly people in 15 communities of the five major administrative regions: Jinjiang, Wuhou, Qingyang, Chenghua and Jinniu, Chengdu city, Sichuan province, this paper uses multiple regression analysis method to analyze the influence of social capital and individual characteristics on life satisfaction of the elderly. The study finds that many aspects have impacts on the life satisfaction of the elderly, such as reciprocity rules in social capital, informal participation, formal social networks, formal participation, interpersonal trust, health status, income level, and whether to live with children. When the factors of social capital and individual characteristics are taken into comprehensive consideration, the influence degree of social capital is greater, and the five factors of social capital have an impact on the life satisfaction of the elderly. However, the influence of whether the elderly live with their children and how much they own among the factors of individual characteristics disappears. Therefore, compared with individual characteristics, social capital has a greater and more sustainable impact on the life satisfaction of the elderly.