[Objective] The ecosystem health of Gahai wetland of South Gansu Province was comprehensively evaluated in order to provide a scientific basis for the management and sustainable development of the wetland.[Methods] Using PSR mathematical model, 18 evaluation indexes were selected from three aspects including pressure, state and response, to construct the health evaluation system of Gahai wetland. Analytic Hierarchy Process (AHP) was used to determine the weight of indicators and to analyze the ecosystem health index.[Results] The health index of the Gahai wetland ecosystem was 0.588 1, which belonged to the sub-health state, and the health index of the pressure subsystem was 0.733 2, which belonged to the health state. The health indexes of the state and the response subsystem were 0.489 3 and 0.567 9, respectively, both of which belonged to sub-health states.[Conclusion] Global climate change and human disturbance have seriously threatened the health of the wetland ecosystem in Gahai. wetland Scientific protection and restoration measures are urgently needed to improve the level of wetland management.