Livable, welfare and community oriented long term care services are the trend of Welfare State development. To ensure the satisfaction of the long term care users, multidisciplinary and mutlisectoral approaches are the vital ways to reach the objectives. Social worker is one of the vital members of the service professionals in the long term care services. However, there is little information to describe and analyze the roles and functions of social workers in the long term care services. The main aims of the present paper are to examine the roles and functions of social workers in the long term care services based the current literature reviews. To begin with the reviewing of role theories, and then to analyze the roles and functions of social workers in different long term care settings. Furthermore, the role stress, role development and different characteristics of social workers comparing with other professionals in the long term care services will be discussed in the present paper.