Abstract: The composites of poly lactic acid (PLA) filled with milled glass fibers (MGF) were prepared via molten blending and compression molding. The effects of MGF contents on the morphology, mechanical properties and melt flow rate of MGF/PLA composites were investigated. The results show that well dispersed MGF were coated by silane coupling agent in matrix, and improved interfacial adhesion between the PLA and MGF was observed. With the increase of MGF, the tensile strength was decreased, and the Young′s modulus exhibited the trend of continuous increase. However, the elongation at break of MGF/PLA composites was increased first and then declined. The MGF led to positive influence on the hardness, but brought on a remarkable negative impact on the melt flow rate of MGF/PLA composites.