We present an experimental study of viscous fingering caused by the displacement of an oil phase by non-Newtonian fluids such as Carbopol ® 940 with and without surfactant (SDS) addition in a radial Hele-Shaw cell. When polymer solutions are injected, a variety of fingering patterns as a function of flow rate are observed, which differ from the classical Saffman-Taylor (ST) instability. We have shown that if surfactant concentration locally decreases the interfacial tension, it also leads to a reduction of viscosity and hence results in an increasing impact on capillary number. We found that surfactant-polymer solutions have wider fingers with increasing flow rates in contrast with Newtonian solutions. Our study also revealed that the relative finger width of both non-Newtonian experiments with and without surfactant converge asymptotically to the same value. We think that this phenomenon is caused by the decrease of surfactant concentration in the vicinity of the tip as the finger is growing so that the shear-thinning features of polymer prevail at long time. The flow rate dependency of surfactant solution behavior is driven by the Newtonian or non-Newtonian nature of the fluid.Surfactant-polymer solutions have wider fingers with increasing flow rates in contrast with surfactant-Newtonian solutions. The asymptotic behavior tends to smooth out the surfactant effect on fingering pattern. For both non-Newtonian fluids, the relative finger width converges practically towards the same value that is 0.4 at large Ca * . We assume that this phenomenon is caused by the decrease of surfactant concentration in the vicinity of the tip as the finger is growing.Ultimately, since the Hele Shaw cell can be seen as an idealized model of fracture, a more significant insight into the behavior of surfactant-polymer solutions in fractures should be obtained from this work.