Abstract: The Jingqiu oilfield is coomprised of an unsaturated layer-shaped oil reservoir with simple structure, multi-oil-bearing formation and big thickness.It has been in high water cut stage as it has been developed for more than ten years.The fine oil-reservoir descripton has been applied in order to evaluate its potentials in the middle and late period of development. In according with its own feature, the description was mainly focused on the reservoir itself including fractionizing sedimentation cell, sedimentary and petrographic microfacies, features of heterogeneity of thick oil layers, petrophysical facies, and distribution of remaining oil, etc. The nerve-network method was used for the first time to simulate and to predict the parameter of physical property, sedimentation and diagenic metamophism, and quantitatively pointed out sedimentary-petrography microfacies. The study of petrophysical facies and the distribution of the remaining oil provided geological foundation for impro-ving its development, and gained good result in the developing implementation