The dramatic social and economic changes in China, in addition to age-related factors, have increasingly eroded the social networks among Chinese older adults. The major purpose of this study was to explore the potential of online communities in helping the older population expand social networks, obtain social support, enhance feelings of social connectedness, and engage in more social activities. Another aim of this project was to test a research model that explains how online community networks benefit the subjective well-being of older participants by applying the theoretical model proposed by Berkmen and Glass (2000) regarding social networks and health. The results of the study enabled us to have clearer understanding of how online communities hold promise for broadening social networks and improving the subjective well-being of this population.