In the current research, focus is on the comparison of Jackson and Tucker (JT) theoretical model to experimental results oflarge amplitude oscillatory shear (LAOS) of immiscible polymer blends. The field of rheology of immiscible polymer blends iscurrently very deficient in LAOS results, especially at moderate to low viscosity ratio values. In addition, most of the theoreticalmodeling that was carried out on LAOS of immiscible polymer blends used the small deformation theory of Maffettone andMinale. The current work adds further knowledge in the field of modeling of immiscible polymer blends by testing the predictionsof the large deformation theory of Jackson and Tucker against LAOS experimental behaviour. LAOS experiments werecarried out for a model immiscible blend composed of two... Newtonian components (polybutadiene and polydimethylsiloxane)at viscosity ratios 1.34 and 0.39 and at volume fraction value 0.2. Data for the first, third and fifth harmonics of the sinusoidalstress response were recorded by FT-Rheological experimental set up. Validation of Jackson and Tucker model was carried outand the experimental results were compared to the JT model. Furthermore, the theoretical predictions of the JT code werecompared to the experiments of Almusallam for two blends at viscosity ratio values of 0.1 and 4.4 at volume fraction value0.21. The experimental results were plotted in terms of the scaling parameters of Reinheimer et al to test the scaling law. TheReinheimer scaling law was developed for viscosity ratio values larger than 2.5 and hence a new scaling law was developed inthe current study taking into consideration the viscosity ratio values less than 2.5.