从人口城镇化、经济城镇化、社会城镇化、空间城镇化4个维度构建城镇化水平评价指标体系，从生态压力、生态治理、生态环境3个维度构建生态安全评价指标体系，依次计算黄河流域九省区城镇化水平指数（urbanization development level index,UDI）和生态安全指数（ecological security index,ESI），并采用灰色关联分析模型和解耦模型对2008—2018年黄河流域九省区城镇化水平与生态安全交互作用机制进行分析研究。结果表明:黄河流域九省区城镇化水平与生态安全整体呈上升趋势，UDI由0.24升至0.58，ESI由0.30升至0.41，但增幅逐渐减缓；城镇化水平与生态安全系统间关联度均高于0.6，处于中等关联与极强关联之间，具有较强的相互作用，人口城镇化对生态安全胁迫作用最大，关联度值高达0.741，生态治理对城镇化发展的约束作用最强，关联度值为0.726；黄河流域九省区城镇化水平与生态安全之间存在着较强的解耦作用，未来生态安全对城镇化发展的约束作用逐渐变强。

Since the 21st century,economic globalization and technological reform have promoted the deep integration of population flow,capital flow,resource flow,and technology flow among countries around the globe.The ecological and environmental problems brought by economic development and population pressure have gradually become global problems.Since China′s reform and opening up,with the rapid urbanization process,China realizes the jumping development of the economy,lacks of enough attention to the ecological environment protection in urbanization,and faces enormous pressure of ecological security, excessive consumption of resources,vegetation degeneration,water pollution and ecological deterioration problems.The Yellow River basin is an important economic belt and grain base in China.With the rapid economic development,the ecological environment has been damaged and the ecological habitat of the river basin has been seriously damaged.Ecological protection and high-quality development of the Yellow River basin was upgraded to a major national strategy in 2019,providing a new opportunity for the basin to explore a synergistic model of ecological protection and high-quality development. To find a new way of high-quality development under urbanization development and ecological protection,it is urgent to clarify the interaction between urbanization and ecological security.The evaluation index system of urbanization level from four dimensions of population urbanization,economic urbanization,social urbanization and spatial urbanization is constructed.The urbanization level and ecological security index of nine provinces of Yellow River basin was calculated using analytic hierarchy process and entropy weight method to determine index.The comprehensive weightand grey correlation model was used to calculate urbanization level and ecological safety criterion layer and index correlation from 2008 to 2018 to clarify the influence of internal factors between the two systems.Finally,a decoupling model is constructed to explore the degree of decoupling between the two systems. The urbanization level and ecological security of the nine provinces and regions in the Yellow River basin showed an upward trend.UDI increased from 0.24 to 0.58,with an average annual increase of 9.23%.ESI increased from 0.30 to 0.41,with an annual growth rate of 3.2%.The correlation between urbanization level and ecological security system is higher than 0.6,between medium correlation and strong correlation,and has a strong interaction.Population urbanization exerts the greatest stress on ecological security,and the correlation value is 0.741.Ecological governance exerts the strongest constraint on urbanization development,and the correlation value is 0.726. The conclusions through an analysis were: 1) Urbanization level and ecological security level continue to grow,but the growth rate gradually decreases,indicating that the development level of the two systems is hindered to different degrees.2) There is a strong interaction between urbanization level and ecological security system,and the constraint effect of ecological security on urbanization development may stronger in the future.3) There is a cyclic alternating phenomenon of expansionary coupling and strong and weak decoupling,mainly with decoupling.Therefore,it is necessary to coordinate the relationship between protection and development,strengthen the investment in ecological management,strictly limit the pollutant discharge of enterprises,and develop green and sustainable industries.A green and sustainable ecological industry chain will be built based on local conditions,the ecological compensation mechanisms will be established and improved,and the constraints and bottlenecks of ecological protection on the urbanization process will be broken.