Melt blending of polycarbonate (PC)/poly (ethylene terephthalate) (PET) rich in PC at absence/present of different type of tranesterification catalysts was carried out by using reactive extrusion method. The thermal, dynamic, and morphological properties were studied. It was found that all blends are formed by a PC matrix and a semicrystalline (12-20% of crystallinity) of PET dispersed phase. The addition of a catalyst in the mixing process promotes a refined and homogeneous dispersion of PET, as well as it enhances the dynamicmechanical behavior of PC/PET blends compared with PC. These effects are attributed to the emulsifying effect of the PC-PET copolymer generated by transesterification. Additionally, this copolymer contributes to the miscibility between phases as demonstrated by the glass transition (Tg) shift of PC phase and PET phase.