Recently, the control of the evolution of polymer blend morphology during processing has received attention because of its great impact on the mechanical, barrier or electrical properties. In general polymer blend morphologies can be divided into two groups: dispersed and co-continuous. In the literature, several papers illustrate that the blend morphology depends on the composition, the rheological behavior of each component, the mixing conditions and the interfacial tension. The models proposed by Veenstra and Yu were used to understand the evolution of co-continuous morphology. In this study, a prediction model of dispersed and co-continuous morphology has been established. Blends of HDPE/sPP, LDPE/iPP, at various PE to PP weight ratios (90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80 and 10:90) prepared by twin-screw extruder were characterized. The interfacial tension was measured by the Palierne model. The shear rate in the extruder was determinedusing theLudovic software. Rheological studies were conducted in an Ares rheometer using parallel plate geometry. The experimental results onthe various blends show a good correlation between the interfacial area and the melt elasticity measured at low frequency. The PE/PP blends were observed by scanning electron microscopy (SEM) using staining agent to enhance electron density contrast. The characteristic dimension of dispersed (R) and co-continuous morphology (lc) were measured from SEM observations to obtain the interface areas as a function of the composition. The results were compared to the interface areas obtained using the predictive model. The model was partially validated and showed that the breakup mechanism was dominated by Rayleigh disturbances.