Poly(adipate⁃butylene terephthalate) (PBAT) was grafted with glycidyl methacrylate (GMA) to prepare PBAT⁃GMA, which was subsequently blended with PBAT and poly(lactic acid) (PLA) to obtain PBAT/PBAT⁃GMA/PLA blends. The effects of PBAT⁃GMA content on the mechanical properties, micromorphology, barrier properties, and degradability of PBAT/PBAT⁃GMA/PLA films were systematically studied. The results indicate that increasing the mass fraction of PBAT⁃GMA significantly enhanced the mechanical properties of the films. When the mass fraction of PBAT⁃GMA is 15%, the tensile strength increased from 15.28 MPa (longitudinal) and 12.51 MPa (transverse) without PBAT⁃GMA to 25.61 MPa (longitudinal) and 19.59 MPa (transverse), respectively. Similarly,the elongation at break improved from 109.23% (longitudinal) and 141.32% (transverse) to 217.63% (longitudinal) and 311.22% (transverse). It demonstrates that the incorporation of PBAT⁃GMA effectively enhanced the compatibility between PBAT and PLA,thereby improving the mechanical properties of the blend. Moreover, with higher PBAT⁃GMA content, the barrier properties of PBAT/PBAT⁃GMA/PLA films were also significantly improved.However,the degradation rate of PBAT/PBAT⁃GMA/PLA films decreased slightly with the increase of PBAT⁃GMA mass fraction, indicating that the durability of the materials was improved.