The dynamic rheological behavior of polystyrene filled with low-melting-point (T-m) Sn-Pb was investigated at temperatures below and above the T-m of the alloy, 183degreesC. In the whole temperature range of interest, there existed a secondary plateau in the plot of the dynamic storage modulus versus frequency (omega) at low omegas, and the influences of alloy content and temperature on the plateau were related to the matter state (liquid or solid) of the alloy. We believe that the secondary plateau observed below the alloy T-m was due to the network-type structure formed by the agglomeration of solid filler particles, whereas the plateau above T-m was due to the deformability and relaxation of the liquid alloy droplets. By analyzing the Cole-Cole diagrams, we suggest that the alloy fillers retarded the relaxation processes for polystyrene melt when the temperature was lower than the T-m. However, there existed two separated relaxation processes when the temperature was higher than the T-m, that is, the high-omega relaxation of the phases and low-omega relaxation of the droplets.