Due to the regional characteristics and special environment of classical Suzhou gardens, ancient and famous trees in these gardens are not only organisms or natural resources, but also witnesses and recorders of history, so they have unique attributes and value of humanistic resources. On this basis, current situation of ancient and famous trees as well as ecological landscapes formed by these trees in classical Suzhou gardens were analyzed, connotations of these trees elaborated, and relevant regulations taken to identify the grade of these trees.