The addition of maleic anhydride grafted polybutadiene (PB-g-MAH) can greatly improve the compatibility of polyamide 66 (PA66)/acrylonitrile-butadiene-styrene copolymer (ABS) blends. Unlike the commonly used compatibilizers in polyamide/ABS blends, PB-g-MAH is compatible with the ABS particles' core phase polybutadiene (PB), rather than the shell styrene-acrylonitrile (SAN). The compatibility and interaction of the components in the blends were characterized by Fourier transform-infrared spectra (FTIR), Molau tests, melt flow index (MFI), dynamic mechanical analyses (DMA), and scanning electron microscopic (SEM) observations. The results show that PB-g-MAH can react with the amino end groups in PA66 while entangle with the PB phase in ABS. In this way, the compatibilizer anchors at the interface of PA66/ABS blend. The morphology study of the fracture sections before and after tensile test reveals that the ABS particles were dispersed uniformly in the PA66 matrix and the interfacial adhesion between PA66 and ABS was increased significantly. The mechanical properties of the blends thus were enhanced with the improving of the compatibility. POLYM. ENG. SCI., 2012. (c) 2011 Society of Plastics Engineers