Abstract: By introducing the definitions of stress and stress ecology and stress classification, the significance and principal contents of the stress ecology were expounded. The symptoms of stressed ecosystems include changes in nutrient cycling, primary productivity, species diversity, individual size of dominant populations, succession direction, incidence of diseases, size of population, and so on. The influences of stress can be mitigated by ecosystem homeostasis mechanisms to some extent and within a certain period. Inability to cope can lead to further dysfunction and perhaps to irreversible breakdown of the ecosystem. Stress ecology can be used as theoretical basis for diagnosis, management, restoration and rehabilitation of ecosystems.