Abstract: The silver/polyacrylonitrile(Ag/PAN) composite was synthesized by aqueous in situ precipitation polymerization. The influence of the reactant ratio on molecular mass of Ag/PAN was investigated by measuring its relative viscosity. The optimized synthetic condition of the as-prepared composite is that the concentrations of acrylonitrile(AN) monomer, AgNO₃ and K₂S₂O₈ are 10%, 0.6% and 2%, respectively. The nano-silver/cyclized polyacrylonitrile (Ag/C-PAN) composite was prepared by the preoxidation of resultant Ag/PAN. The components, and also the relative cyclization indexes of nano-Ag/C-PAN composite at different preoxidation temperatures and times were analyzed by FTIR spectrum. The microstructure of the as-prepared composites was characterized by TEM and XRD. The results show that silver nanoparticles with diameter about 10 nm and appeared as face-centered cubic crystal are homogeneously dispersed in the cyclized PAN matrix.