Abstract The aim of this research is to study the mechanical, thermal properties and morphology of polybutylene adipate- co -terephthalate (PBAT) blended with polyethylene terephthalate (PET) thin films. Effect of TiO 2 and ZnO is also investigated on mechanical and thermal properties of PBAT/PET thin films. PBAT and PET are blended by a twin screw extruder and film is casted by film extruder. Mechanical, thermal properties and morphology are studied by using universal testing machine, differential scanning calorimeter, thermogravimetric analyzer and scanning electron microscope. From the results, higher PBAT content led to the increment of elongation at break with the sacrifice of modulus of PET thin films. In addition, thermal stability of PBAT/PET thin films is lower than neat PET films. Moreover, modulus and tensile strength could be improved by adding 1-2 wt% ZnO into PET/PBAT film. However, the addition of TiO 2 has no significant effect on tensile properties of PET/PBAT film.