Polyarylene ether nitrile (PEN)/polyphenylene sulfide (PPS) blends were prepared via a melt-mixing process. The melting flow properties, compatibility, thermal and mechanical properties were characterized by melting index test, dynamic mechanical analysis (DMA), thermal analysis, tensile test and the fracture suface morphologies. The melt-mixed PEN/PPS blends displayed the excellent melting flow properties during processing. With the content of the PPS increased in the PEN, the melting index of the blends increased considerably, which is beneficial to the processability of PEN. PPS was found to be incompatible with the PEN by the DMA and DSC results. Morphology examinations reveal that the PPS phase is randomly dispersed as droplets with an average size of about 1~2 μm in PEN matrix, which is the main reason to enhance the toughness of PEN. Importantly, the blending materials maintained the characteristic thermal and thermo-oxidative stability as well as mechanical properties of the PEN as considering the further commercial applications.