Abstract: The reserve?production ratio (RPR) is an important index to reflect the reserves guarantee degree of a country, a region or an oilfield. By analysis of RPR, we can judge whether an oilfield is sustainable for development or not, and whether its resources succeeding is in virtuous circle. In this paper, the relationship between RPR and production decline amplitude or recoverable reserves variation is analyzed and the RPR variation of multi?configuration oilfield is presented. On the basis of the production decline amplitudes and reserve?production equilibrium coefficient changing ranges of different configuration oilfields, the reasonable RPR changing ranges of the oilfield that satisfies some quantity of output scale are determined using orthogonal experimental design principle