Abstract: MCC/PLA/PPC composites were prepared by melt blending using PLA grafted with maleic anhydride (PLA-g-MAH) as a compatibilizer and MCC as a modifier. The effect of MCC on the mechanical properties, heat resistance and thermal stability of MCC/PLA/PPC composites were investigated by temperature-controlled stretching, dynamic thermal analysis, scanning electron microscopy and thermogravimetric analysis. The results shown that the tensile strength flexural strength was improved by 12.7 % and the glass translation temperature was increased by 9.8 ℃ when 40 wt% of MCC was added. On the other hand, the addition of 5 wt% PLA-g-MAH made the composites an increase in tensile strength by 53.7 %, in flexural strength by 43.1 % and in impact strength by 18 % due to an enhancement in interfacial adhesion. In this case, the breaking strength of the composites was also improved by 80 % at 60 ℃. Moreover, the thermal degradation temperature and maximum weight-loss temperature of the composites were improved by 25.31 and 61.83 ℃ compared to PLA/PPC composite, respectively.