Possessing abundant natural resources was the basis of social and economic development to any country or region. Therefore, a coordination state between social-economic development and resource-environment base was the first task and aim for most of countries and regions. In this paper, Resource and Environment Assessment Formula(RCER) was introduced and five fundamental elements including arable land, forest, grassland, energy and water resource were selected to evaluate resource-environment base and man-land relationship with Gansu province as a case. Result showed that Compared with the average level, there had been a fragile resource-environment in Gansu province. The resource and environment condition per unit area of Gansu province was very low, especially for water resource, the number of per unit area and per capita was only 7.23 percent and 43.12 percent of  the whole country, respectively. The serious water condition had been becoming the most significant factor hindering the social and economic development. At present, the man-land relationship pressure index was very low, its average value in recent years was 0.0337. However, with the population growth and rapid economic development the man-land relationship pressure index would increase form 0.0353 in 2002 to 0.2577 in 2020, the pressure between man and land would increase 6.3 times in the coming 10 years, and most of them have been brought about from economic development. The man-land relationship in Gansu province would come into a more strained stage in the future and the rapid economic development was the main driving factors to the man-land relationship. It was necessary that some regional policies should be readjusted to realize a sustainable development for Gansu province: 1) implementing a low population increase plicy to ensure the sustainable utilization of resources and environment; 2) accelerating the transfer of rural labors; 3) improving the efficiency of resource-use through speeding up regional economic structure deeply and changing the economic development model; 4) increasing capital input and ensuring stabilization and improvement of environment, and basing resource exploitation on environment protection; and 5) promoting the social adaptive capacity and using social resources to relieve the pressure of mankind on resource and environment.