Poly(phenylene sulfide) (PPS) was melt blended with Nylon66 and the mechanical properties and corresponding fracture morphologies were investigated. The thermal distortion temperature (HDT) of PPS/Nylon 66 blend showed that the inherent thermal stability of pure PPS can be maintained up to 30 wt% Nylon66, but then it started to decrease linearly thereafter to that of pure Nylon66 based on the rule of mixtures relationship. Tensile tests of PPS/Nylon66 blends at testing temperatures of -30, 25, 75, and 150 degrees C showed that the maximum stress decreased up to 30 wt% Nylon66, and started to increase thereafter. Strain at break showed little change at low nylon content regardless of testing temperature, however, a large strain at break increase could be observed at more than 30 wt% Nylon66 and at 150 degrees C testing temperature. At the same testing temperatures, the impact strength of PPS/Nylon66 blends was investigated, and it was found that an impact strength increase at all testing temperatures could be observed at more than 30 wt% Nylon66.