The library is a prominent constituent of the spiritual civilization construction, which bears the important task to educate the citizens, and it is vital in fostering and enhancing the citizens' cultural quality. This :paper begins with the social functions of the public libraries and their relations with social responsibilities, and then it analyzes the responsibilities of the public libraries to the public and society, and then expounds how to raise the responsibility-consciousness of the public libraries so as to fulfill the social responsibilities of them better.