Abstract: Interbedded layer is one of the most important reasons for serious reservoir heterogeneity, especially for the oil filed with a long production history. The remaining oil distribution is controlled by the genetic type,spatial distribution and reservoir heterogeneity. In the view of the characters of Donghe Sandstone, such as low resistivity, heavy heterogeneity, on the basis of core and log, the interbedded layer of HD4 oil filed have been divided into three kinds, including calcareous interlayer, argillaceous interlayer and calcareous argillaceous sandstone interlayer, most of them are calcareous argillaceous sandstone interlayer, followed by calcareous interlayer, with argillaceous interlayer at least. The criteria for identification of interbedded layers with logging data have been established for this block, and the vertical interlayer have been identified. The work has an important and practical significance for selecting advisable series of development layers, making the best exploitation plan,enhancing oil recovery, improving effect of development and searching for favorable exploration blocks and development measures for HD4 oil filed.