The room temperature brittleness has been a long standing problem in bulk metallic glasses realm.This has seriously limited the application potential of metallic glasses and their composites.The elastic deform-ation behaviors of metallic glass matrix composites are closely related to their plastic deformation states. The elastic deformation behaviors of Cu48-xZr48Al4Nbx(x=0, 3 at.%) metallic glass matrix composites (MGMCs) with different crystallization degrees were investigated using an in-situ digital image correlation (DIC) technique during tensile process.With decreasing crystallization degree, MGMC exhibits obvious elastic deformation ability and an increased tensile fracture strength.The notable tensile elasticity is attrib-uted to the larger shear strain heterogeneity emerging on the surface of the sample.This finding has impli-cations for the development of MGMCs with excellent tensile properties.