Complex fault-block reservoirs have thin oil-bearing series and complex development of isolated interlayers. Therefore, the distribution of residual oil under the control of multiple interlayers is of great significance to the decision of potential exploitation measures for water-driven complex fault-block reservoirs. Based on the typical model, the influences of the number of interlayers (across injection and production wells), the size of interlayer development and the location of interlayer distribution on the vertical sweep efficiency and residual oil distribution of reservoir after water flooding were studied. Then, according to the reservoir characteristics of complex fault block reservoirs, 16 kinds of multi-interlayer displacement models simulating the number and distribution of different interlayers between injection and production wells were established, and they were classified into two displacement modes: "less to more more to less classification method of multi-interlayer displacement mode and the law of oil control, this paper puts forward some potential exploration countermeasures such as perforation adding and new well deployment for typical blocks, and obtains good recovery performance. The conclusions and its success application can provide reference for other multi-layered reservoirs in high water-cut period of residual oil exploration.