In this study, st),rene-b-ethylene/butylene-bstyrene triblock copolymer (SEBS) and maleic anhydride grafted SEBS (SEBS-g-MA) were used as compatibilizers for the blends of polyphenylene sulfide/nylon 66 (PPS/PA66). The mechanical properties, including impact and tensile properties and morphology of the blends, were investigated by mechanical properties measurements and scanning electron microscopy. Impact measurements indicated that the impact strength of the blends increases slowly with elastomer (SEBS and SEBS-g-NLA) content upto 20 wt %; thereafter, it increases sharply with increasing elastomer content. The impact energy of the elastomer-compatibilized PPS/ PA66 blends exceeded that of pure nylon 66, implying that the nylon 66 can be further toughened by the incorporation of brittle PPS minor phase in the presence of SEBS or SEBS-g-MA. The compatibilization efficiency of SEBS-g-MA for nylon-rich PPS/PA66 was found to be higher than SEBS due to the hi situ forming SEBS interphase between PPS and nylon 66. The correlation between the impact property and morphology of the SEBS-g-MA compatibilized PPS/ PA66 blends is discussed. The excellent impact strength of the nylon-rich blends resulted from shield yielding of the matrix. (c) 2007 Wiley Periodicals, Inc.