Maleic anhydride grafted poly(lactic acid)(MPLA)was prepared by twin-screw reactive extruder,the processing technology of extrusion was studied,and the property of the prepared product was tested.The results showed with increase of the concentration of initiator and the rise of the rotating rate of the screws,the main trend of the intrinsic viscosity and the melt flow rate were declining first and then increasing,while temperature had little influence on the process.The MPLA prepared by twin-screw reactive extruder had good hydrophilicity and interfacial compatibility.