Abstract: Based on the planar radial flow equations and material balance equations, the relational expression between water cut and water saturation was derived from oil field data? and from the theory of reservoir engineering and percolate mechanics, and then the relationships between the water saturation and the water was derived. According to the water-oil discharge equation,the model may predict remaining oil saturation of single-well and the remaining oil distribution in the whole reservoir or unit.It is proved the reliable supports for the next development.

Key words: two-phase percolation flow, material balance, water-oil discharge, oil field data, remaining oil distribution