AbstractCarbon fiber reinforced epoxy composites toughened with carboxyl terminated acrylonitrile butadiene rubber (CTBN) and hydroxyl terminated polyester (HTP) were prepared by autoclave vacuum bag molding process. The influence of compositions and blending method with toughening agents on glass transition temperature (Tg) and impact energy of cured laminates was evaluated. To improve the blending capability, different pre‐treatment methods were adopted for CTBN and HTP. The toughness of the carbon fiber reinforced epoxy composite materials (C‐FRP) modified with HTP showed a maximum when the HTP contents was 3.1 wt%. In case of CTBN, the maximum was 5.7 wt%. In addition, the fracture surfaces of toughened epoxy resin were examined by scanning electron microscopy (SEM) and the morphology was also discussed in this study.