The prime objective of this paper is to provide a simple but effective and economic route to prepare tough PLA materials based on physical melt-blending of PLA with EVA copolymers. The effect of both the VA content in the EVA copolymer and the EVA copolymer content in the blends on the toughening was examined. The toughening mechanism was studied based on the analysis of the local deformation mechanism by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS).