To resolve the problem concerning long-and mid-term ecological scheduling of reservoir groups, the Xinjiang Irtysh river basin was selected as the study object, and a network node map for reservoir scheduling was established. Long-and mid-term simulated reservoir group and optimum scheduling model oriented ecologies were established, and the two models were solved using the self-iterative optimal simulation and improved DP algorithms based, respectively, on water balance and big system methods. Results of the study demonstrate that the obtained water supplement adequately meets demands concerning comprehensive water-resource utilization, ecology usages, and the corresponding guarantee rate. Results obtained using the optimum model when applied to ecologies existing within and outside of the Xinjiang Irtysh river, Wulungu lake, Beijiang and agricultural irrigation was observed to be better compared to those obtained using the simulated model. At the same time, the relationship between incoming water and ecological supplements was revealed, and a reservoir operation chart was drawn. Additionally, an operational equation, which passed the rationality test, was set up. Results obtained in this study bear critical significance with regards to providing long-and mid-term strategies for comprehensive utilization of water resources and protection of the ecological security for the fish habitat and valley forests and grassland.