Abstract: During long term water injection period, both the pore texture and oil saturation of reservoir have changed, resulting in the development of water flooded layers.It is a difficult matter to conduct interpretation of water flooded layer with logging data during oil field development.According to analysis of this study, log responses are quite different before and after oil layer been water flooded.In addition, for different sedimentary microfacies, their physical properties of reservoir before and after water flooding are also quite different.Therefore, water flooded layers can be identified by conventional log analysis or by multidisciplinary analysis with conventional and special log data.For the interpretation results, validity check can be carried out by a series of method such as log characters comparison of adjacent-wells, production performance data study, sealed coring data analysis, sedimentary microfacies division and multiwell comprehensive evaluation and so on.