Rheological properties of four binary blends miscible in the melt of polyamide 6, with an amorphous aromatic copolyamide and three poly(olefinic) polymers (iPP, iPB, and HDPE) with petrolic resin, have been examined. In addition, we investigated the rheological behavior of blends that were not miscible, such as iPP with PA6, when compatibilized with different amounts of an interpolymer (iPP modified by grafting with maleic anhydride) to improve their interfacial adhesion.