The addition of polymer to injection fluid increases the crude oil recovery by improved sweep efficiency. Although it is the most widely used method for chemical enhanced oil recovery (CEOR), limitations such as lower stability of the polymer under reservoir conditions hinder the efficiency of the process. In the current study, a novel nanoparticle assisted polymer flooding approach was carried out to overcome these limitations. To determine whether nanoparticles influence the displacement efficiency of the injected fluid, we used a blend of xanthan gum and nickel nanoparticles. We have evaluated the changes in the dilute solution viscosity of xanthan when the nickel nanoparticles are added and have found out that a xanthan-nickel nanoparticles mixture has a higher intrinsic viscosity of 55.25 dL/g compared to 49.13 dL/g for the gum solution. Efficiency of nanoparticle assisted polymer flooding was evaluated in sand packed bioreactors with similar to 0.6 PV of residual oil in place (ROIP). Flooding results demonstrated the highest recovery of 5.98% of additional ROIP with xanthan-nickel nanoparticle mixture compared to 4.48 and 4.58% of ROIP during the separate flooding of xanthan and nanoparticles, respectively. Results suggested the novel nanoparticle assisted polymer flooding approach is able to increase oil recovery beyond available methods.