Abstract: Unsteady method has been applied to measure the polymer flooding relative permeable curve.The so called "J.B.N" experimental data has been improved and compared with water flooding.The result shows that the oil curve ascends while the water curve descents compared with water flooding,end point of oil curve moves rightwards while the water curve lower than water flooding,the end point of water curve is lower,the cross point of relative permeable curve moves left ward and descends.The breakthrough recovery of polymer flooding is much higher than water flooding,when the polymer solution breakthrough,the water cut increases rapidly than water flooding.The result reflects the flow regular pattern of polymer and oil flooding,this paper provides important parameters and reference for the numerical simula-tion,performance prediction and effect evaluation of polymer flooding.