Abstract: Varying weight fraction of multi-walled carbon nanotubes were incorporated into Sn-58Bi soler alloy by ball-milling and low temperature melting methods, the morphologies of carbon nanotubes in solder alloy and the influences of carbon nanotubes on the pull-off strength were investigated by SEM, EDS, and DSC. The experimental results indicate that part of carbon nanotubes are incorporated into Sn-58Bi soler alloy after ball-milling and low temperature melting; 0.03% CNTs can improve the wettability; the melting point of Sn-58Bi-CNTs solder does not change much; the dispersive distribution of carbon nanotubes could refine the microstructure of Sn-58Bi-CNTs joints and the reliability of solder joints also is improved by the influences of CNTs on the fracture mechanism of solder joints.