This study aimed at evaluating the effects of the incorporation of micro and nanoparticles of CaCO 3 on the properties of poly(vinyl chloride) (PVC), intended to industrial application. The PVC compounds added with particles of different sizes were achieved in an intensive mixer. Rheological, microstructural, mechanical and thermal properties of the compounds obtained were evaluated. The rheology test showed that the compound with the addition of two-particle size plasticized faster compared than other formulations. Microstructural analysis showed a poor particle size distribution for the micro-CaCO 3 charges, and the nano-CaCO 3 samples have agglomerated particles. The thermal analysis showed the compound added with two particle size with higher gelation, and in the loss modulus E' and E", the values also were close. The analyses showed that the combination of the two-particle sizes presented superior results when compared with the micro or nano used singly.