Abstract: In order to study the coupling and coordination process and laws between natural resources and social economy in the Lower Heihe River Basin in recent 40 years, the authors have taken Ejina Banner as the research object. According to the natural resources and social economy data in the Ejina Banner Statistical Yearbook (1990-2015), the authors have established an indicator system to study the comprehensive development level. The coupling and coordination degree between natural resources and social economy have been analyzed based on the coupling coordination degree model, and the coupling and coordination degree from 2020 to 2030 has been predicted. The results show that the comprehensive development level of natural resources in Ejina Banner has increased from 0.160 0 in 1990 to 0.811 5 in 2015 with an obvious increasing trend. The comprehensive development level of social economy has increased from 0.115 0 in 1990 to 0.713 8 in 2015, also with a continuous increasing trend. Overall, the comprehensive development level curves of the natural resources and social economy are similar. The degree of coupling and coordination between natural resources and social economy has shown an upward trend, which transferred from severely unbalanced economic gain and loss type in 1990 to highly coordinated development synchronization type in 2015, through the antagonistic, development and running-in phases. The coupling and coordination degree between natural resources and social economy would improve in the next 10 years, based on the prediction by the gray theory GM(1,1) model.