Abstract: The method of rapid prototyping oriented by jet electroforming was used to prepare bulk nanocrystalline copper.The surface morphology,microstructure,grain sizes of the copper deposit were studied by means of SEM and XRD,and the mechanical properties of nanocrystalline copper were also measured.The results show that the average grain size of the bulk nanocrystalline copper fabricated with current density of 300 A·dm-2 is about 47.4 nm,the tensile strength and tensile ductility of the nanocrystalline copper reache to 470 MPa and 14%,the tensile strength is about 3.6 times of the one of the coarse crystalline copper.