Abstract: Low permeability oilfield’s dimensionless fluid productivity and productivity indexes variation characteristics have very big difference compared with high permeability oilfield，so high permeability oilfield water flooded layer’s defined standards cannot be applied to low permeability oil field. Otherwise，it will affect the productivity prediction of different levels of water flooded layers and the development of reasonable measures for tapping potential. In order to reduce the mutual crisscross between water flooded level and water?cut development stage with different boundaries，and make different types of reservoirs or the same reservoir be comparative between them，this paper proposes methods for determination of water flooded level limit in terms of the water?cut development stage，identification of the flooded levels，prediction of productivity and evaluation of remaining oil potentials by means of relative permeability curves. The case study indicates that by different water flooded layers testing，the water production rate is consistent with the prediction results，being worthy of reference for other oilfields