Abstract. This paper proposes an ecosystem services–based integrated water resource management (IWRM) framework within which a participatory Bayesian network (BN) model that assists with the integration of IWRM is developed. The framework is divided three steps: (1) identifying water-related services of ecosystems; (2) analysis of the tradeoffs and synergy among users of water; and (3) ecosystem services–based IWRM implementation using the BN model. We present the development, evaluation and application of a participatory BN model with the involvement of four participant groups (stakeholders, water manager, water management experts, and research team) in Qira oasis area, Northwest China. As a typical catchment-scale region, the Qira oasis area is facing severe water competition between the demands of human activities and natural ecosystems. We demonstrate that the BN model developed provides effective integration of ecosystem services into a quantitative IWMR framework via public negotiation and feedback. The network results, sensitivity evaluation, and management scenarios are broadly accepted by the participant groups. The intervention scenarios from the model conclude that any water management measure remains unable to sustain the ecosystem health in water-related ecosystem services. Greater cooperation among the stakeholders is highly necessary for dealing with such water conflicts. In particular, a proportion of the agricultural water saved through improving water-use efficiency should be transferred to natural ecosystems via water trade. The BN model developed is appropriate for areas throughout the world in which there is intense competition for water between human activities and ecosystems – particularly in arid regions.