Abstract: In the development of oilfield A, Bohai area, accurate description of connectivity of sand bodies is closely related with the reasonable layout of injection-production pattern and the improvement of recovery ratio. The reservoirs in oilfield A are mainly point bar, natural barrier, and crevasse splay. In addition, there are many thin sand bodies. Aiming at this situation, we have adopted a series of effective technologies to study the connectivity of sand bodies, including logging data statistics, strata slice technology, and multi-attributes cluster analysis, etc. The results show that these technologies can well interpret the problems existing in oilfield development. Some former interpreted independent sand body was found un-connected in oilfield development, which is actually overriding of two or more sand bodies. In terms of the re-interpreted connectivity, the injection wells were adjusted, and the injection-production pattern was optimized. Injection-production sample shows that the above mentioned method can well solve the problem of describing sand body connectivity in fluvial facies oilfield so as to improve the recovery ratio.