The relative permeability curves of polymer flooding are important bases for the development index predicting the polymer flooding oilfield. Aiming at the low numerical simulation accuracy caused by the lack of the relative permeability of the polymer flooding in the offshore L oilfield

we determined the relative permeability curves of the polymer flooding by the non-steady-state method to compare the relative permeability of different core permeability and polymer concentration. The variation law of relative permeability curve of the polymer flooding was summarized as well. The experimental results showed that the permeability curves of the polymer flooding increased with the core permeability

the relative permeability of the oil phase decreased with the same water saturation

and the residual oil saturation also decreased. With the increase of the polymer concentration

the oil relative permeability of the same water saturation increased

but the residual oil saturation decreased. In the early stage of polymer flooding

the residual oil saturation decreased rapidly

while in the middle and late stages

the residual oil saturation decreased slowly. The research results provided guidance and basis for fine numerical simulation and development planning in offshore polymer flooding fields.