Polymer flooding is the more successfully and mature chemical EOR technique (Manrique, 2007), The success of polymer flooding as a method of oil recovery has been attributed to a profile control mechanism between polymer solution and oil during water flooding. Two important parameters are important on this process: Mobility Ratio (M) and Capillary Number (Nc) (Thomas, 2007, Karpan, 2011). As polymers are injected in the reservoir, they are exposed to chemical, physical and mechanical degradation that affect their performance in sweeping the crude oil trapped in the porous medium. The effect is critical under high salinity brine with divalent ions Ca2+ and Mg2+. The object of this research was to study the effect of flow behaviour of HPAM (hydrolysed poly-acrylamide) of different molecular weight (MW) and special co-polymers PAM as chemical flooding of sandstones core rocks under high salinity conditions, and under harsh conditions of brine composition existing in the North Sea
