In this paper, the adhesion at the interface between two nanofillers (montmorillonite and CaCO3) anda polymer matrix (PP) in a ternary polymer nanocomposite is analyzed by modeling of mechanical properties. Also, Sato-Furukawa model is simplified for calculation of tensile modulus in the ternary nanocomposites. Moreover, linear and quadratic models are well examined for yield strength of the ternary samples. A good agreement is observed between the experimental results and the predictions, which validate the current modeling for a ternary system. Although the present ternary samples contain a high content of nanoparticles, the theoretically obtained parameters by several models confirm the existence of a good interfacial adhesion between both nanofillers and PP matrix. Additionally, all studied models demonstrate the largest level of interfacial bonding in samples containing 4 wt% of MMT and different CaCO3 contents (2-20 wt%). (C) 2014 Elsevier B.V. All rights reserved.