Light diffusing materials consisting of semicrystalline polypropylene (PP) and ethylene vinyl acetate copolymer (EVA) with tuned optical diffusion were successfully prepared through melt compounding technology. With increasing the EVA content, the optical properties of PP/EVA blends were enhanced, such as the transmittance and haze of the blend were enhanced simultaneously, the light diffusing patterns became homogeneous. On the contrast, when the EVA content beyond 50%, the optical properties turned to become deteriorated. DSC results revealed that the addition of EVA had little influence on the crystalline and melting behaviors of PP, while SEM images showed that the size of EVA phase tended to become enlarged with increasing the EVA concentration. Thus, the size of light diffusing phase was considered to play a crucial role in determining the optical properties of the blends, which was further demonstrated through Mie scattering theory. The significance of this work was providing a potential candidate of light diffusing material based on semicrystalline polymer.