This paper introduced and analyzed the development status and characteristics of intergenerational programs (IPs) in American public libraries through e-mail, telephone, face-to-face interviews and field observation. The number of IPs in American public libraries was limited, but the types were diverse. The most common reason for IPs was based on the effective match between problems or unmet needs and available resources in the community, the main beneficiaries were the vulnerable or underserved elderly and young people, the core idea was to promote mutual support and develop mutually beneficial relationships between older and younger people. The common features of IPs included emphasizing equality and reciprocity among participants, giving participants full autonomy, focusing on cooperation with different departments and institutions, and children's and youth departments as the primary sponsoring departments. This paper analyzed the influence of IPs from the perspectives of the young, the old, the library and the community.