Abstract: Building socialist harmonious society is closely linked with ethics spirit. Due to its functions in norm, coordination and innovation, system ethics provides a harmonious society with reasonable, fair system environment and ethics support.It also plays an important role in promoting society fairness and people's freedom developed in an all-round way. This value orientation accords with that of harmonious society. As a matter of fact, the task of building a harmonious society can also provide the corresponding value demands on system ethics in the following aspects, such as political, economical and social structure.