Abstract: BZ oilfield in the Bohai sea is a medium-sized conventional fluvial facies oilfield, which characterized by irregular shape of single sand body, big differences on reserves scale, rapid lateral change of reservoirs, and multiphase mutual superimposed characteristics of channel sand bodies in vertical direction. In view of the characteristics mentioned above, an efficient development mode and strategy suitable for the oilfield are explored. In the early stage, layered well spacing of single sand body with horizontal wells was adopted. In the middle development stage, potential tapping of untapped reserves with horizontal wells was adopted. In high water cut stage, potential tapping of residual oil inside well pattern based on reservoir configuration was adopted. The horizontal well development mode of BZ oilfield has realized stable production for many years, and the water flooding development index has kept good.According to the evaluation criteria of water flooding indexes in Bohai oilfield, the evaluation process of two key water flooding indexes, namely the rise rate and decline rate of water cut, was optimized. The obtained results were applied to BZ oilfield and the evaluation criteria are all of the same standard.