Copolyamide 66/6T/610 was synthesized by the condensation polymerization of polyamide 66, 6T, 610 salts. Copolyamide nanocomposites containing well-dispersed multi-walled carbon nanotubes (MWNTs) were prepared using a solution mixing method. The crystallinity increased with increasing MWNT content, suggesting that MWNT can help the copolyamide crystallize further. The copolyamide/MWNT nanocomposites also showed improved mechanical properties and electrical conductivity. Scanning electron microscopy of the fracture surfaces of the composite showed not only a uniform dispersion of MWNTs but also strong interfacial adhesion with the matrix, as evidenced by the presence of many broken but strongly embedded carbon nanotubes in the matrix.