Abstract: PS/AlNPs composite fibers were prepared by adding AlNPs into PS to finish the simulation study of conductive matrix materials for Z-pinch: deuterated polystyrene/nano-aluminum (DPS/AlNPs). The effects of temperature and shear rate on the rheological properties, the relationship between the structural changes, the flow condition of composites melt and the properties of PS/AlNPs, as well as the morphology, thermal stability and mechanical properties of PS/AlNPs fiber were investigated. The results show that the PS/AlNPs melt is a typical shear thinning non-Newtonian fluid, and the apparent viscosity of the melt is negatively correlated with the temperature. The composite possesses non-Newtonian index of between 0.462 and 0.546 at 240-260 ℃, the coefficient of viscosity of about 1.8 to 2.1, and the activation energy of viscous flow sitting between 77.2 and 104.6 kJ mol^-1, showing its good spinnability. The PS shows its ability to coat AlNPs very well and prohibits the AlNPs being oxided, giving birth to a PS/AlNPs fiber possessing smooth surface. The fiber has the biggest elongation at break and the highest breaking strength when the content of AlNPs is 1% and 5%, respectively.