Abstract: Ecological water use safety is the primary condition for maintain river health. In this paper,according to the characters of river ecosystem,the concept of ecohydrological regime is proposed,and the multi-parameter system of the ecological water requirements(minimum and appropriated ecological water demand,ecological water requirement in flood season)are established,which are regarded as flow requirement for river health.According to the ecohydrological regime the integration of ecological water requirements can be referred to ecological with temporal characters.Based on the ecological flow regime,therefore,the warning mechanism as well as the regulation and managenent rules of ecological water use are discussed.The results of the case study in the mid-lower reaches of the Yellow River can be scientific supports to maintain security of the ecological water used in that region.