Abstract: PLA/PBAT blends with various loadings of PBAT and chain extender ADR were prepared by a twin-screw extruder at different processing conditions，including twin-screw speeds and die temperature. Phase morphology of the resultant blends were observed by SEM. And their impact properties were tested also. It is shown that the toughness of PLA was improved a lot with the addition of PBAT, and the fractured surfaces of PLA/PBAT with ratio of 85/15 exhibited roughened feature. The impact strength of PLA/PBAT(85/15)increased by 320%while the loadings of chain extender ADR is 0. 6%.With the increase of twin-screw speed，the impact strength of the blend increased，and reached its best value 0. 45 kJ/mz at the speed of 80 r/min.