Ag/Cu composite wires were prepared by a solid-liquid casting method and drawing. The influence of annealing temperature on interface and mechanical properties of the Ag/Cu bimetal composite wires was investigated. The Ag/Cu interface was analyzed by scanning electron microscope and optical microscope to investigate the microstructure, elements distribution and bonding level. The effect of annealing temperature on diffusion thickness was also analyzed by EDS and line scan. The results show that the width of the diffusion region along the interface in the both sides increases with higher annealing temperature. Good bonding properties of the interface could be obtained when the optimal annealing temperature is 400 oC ~ 500 oC and the holding time 60 min.