The effect of injection molding conditions and reactive compatibilization on the morphology of maleic anhydryde-modified poly(phenylene oxide)/polyamide-6 blends was investigated. The injection flow rate primarily influenced the position of the subskin layer, and the injection temperature affected the aspect ratio of the dispersed phase. A reduction of the size of the dispersed phase occured during the converging flow in the barrel-to-sprue zone. The reactive compatibilization reduced the flow induced deformation, the coalescence and the breakup of particles and improved the dispersion of the minor phase.