Two compositions were selected for investigation of effect of clay and n-butyl acrylate glycidyl methacrylate ethylene terpolymer (PTW) as compatibilizer on thermal properties and non-isothermal crystallization behavior of PP/PLA/ clay nanocomposite systems, i.e., PP-rich one (75/25 composition) containing Cloisite 15A and PLA-rich one (25/75 composition) containing Cloisite 30B.