Clay-polypropylene (PP) nanocomposites (NCs) were prepared by melt processing. Two types of PP with different levels of crystallinity were used. Mixtures of the two PPs were made at different ratios that generate a varying degree of crystallinity for the final NC samples. The level of micro- and nanodispersion of the organoclays and the microstructure of the resulting NCs were characterized by means of various techniques, including X-ray diffraction analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and differential scanning calorimetry (DSC). The results have demonstrated the impact of crystallization on the level of clay intercalation. The mechanical performance of the nanocomposites was also evaluated, but a direct relationship between intercalation and mechanical properties cannot be established because of the difference in the mechanical properties of the two PP matrices.