Vistamaxx performance polymer which is one type of propylene-based elastomer acting as the flexibilizer for toughening the homopolypropylene (HPP) was studied using X-ray scattering at wide, small, and ultrasmall angle regimes and dynamic mechanical analysis techniques. The well-overlapped scattering curves at wide angle and ultrasmall angle indicate the unaffected structure on the atomic scale and hundreds of nanometer scale for all the compounds. The different scattering intensity at the moderate scattering vector indicates the existence of heterogeneities induced by the flexibilizer on the nanometer scale from 20 to 100 nrn. The flexibilizer exfoliated the lamellae from the periodic stacks in HPP. The heterogeneities could be ascribed to the phase-separated flexibilizer and the exfoliated lamellae. The phase-separated flexibilizer domains block the formation of the complete crystalline skeleton that lowers the storage modulus of the compounds compared with the pure HPP.