Abstract: The PPS/PA66matrix composites with short glass fiber (SGF) and long glass fiber (LGF) were prepared in this work.Although the addition of PA66 led to a dramatic decrease in mechanical properties of PPS, the PPS/PA66/SGF composites presented slightly better mechanical properties than the PPS/SGF ones.On the other hand, the mechanical properties of PPS/PA66/LGF composites were much better than those of the PPS/SGF ones.It was proposed that the incorporation of glass fiber into the PPS/PA66 blend could make a stable rigid interlocked structure between two resins.Such an interlocked structure was confirmed by scanning electron microscopic observation and dynamic mechanical analysis.Compared to the PPS/SGF composites, the PPS/PA66/LGF ones presented a longer fiber length in the flow direction, thus leading to better mechanical properties.