Polymeric materials with improved properties can be obtained through polymer blends. As a polymer mixture is generally immiscible and incompatible, it is necessary to use compatibilizers to improve the interfacial adhesion. Polyamide 6 (PA-6) is an attractive polymer to engineering applications; however, it reveals processing instability and relatively low-notched impact strength. This behavior can be modified by blending with acrylonitrile-butadiene-styrene (ABS) copolymer. In this study, blends of PA-6 with ABS were prepared using gamma irradiation, and the effects of ABS and ionizing radiation on the properties of PA-6/ABS blends were investigated by differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) techniques. The data showed that the presence of ABS (30 wt%) in the blend decreased the tensile strength and elongation at break with respect to pure PA-6. The decrease in the mechanical property was observed at doses 30 and 50 kGy. ABS showed strong effect on the crystallization of PA-6 in the PA-6/ABS binary blends. All irradiated blends are thermally more stable than those non-irradiated. Chemical changes can be clearly seen in FTIR spectra through two bands assigned for N-H and OH- groups. POLYM. ENG. SCI., 48:373-380, 2008. (c) 2007 Society of Plastics Engineers.