Glass fibers grafted by hyperbranched polymer with amino terminal group, GFs-HBPA, were incorporated into an epoxy matrix to prepare a high-performance composite. Mechanical characterization of epoxy-based composites was performed to investigate the effect of GFs-HBPA in the epoxy matrices. The composites revealed significant improvements in flexural strength, elongation at break, and tensile strength, as well as impact resistance in comparison to the neat epoxy. For instance, the flexural strength, elongation at break, tensile strength, and impact strength for composite with 2 wt% GFs-HBPA were increased by about 17.7, 158, 7.9, and 35.9 %, respectively, in relation with the neat epoxy. The reinforcing effect of GFs-HBPA was analyzed on the fracture surface of composites through field emission scanning electron microscopy.