Abstract: Single crystal pure copper bars with large-diameter were prepared by a self-developed vacuum melting and argon protecting continuous unidirectional solidification equipment, the effects of process parameters on their solidified structure and surface quality were investigated, and their mechanical properties and electrical properties were tested and analyzed. The results show that single crystal pure copper bars of φ16 mm with bright surface can be continuously and stably produced under the conditions of the melting temperature of 1 150℃ to 1 180℃, the mould outlet temperature of 750℃, the cooling water volume of 900 L·h^-1, the cooling distance of 50 ram, and the drawing speed of 9 mm·min^-1. The tensile strength, elongation and conductivity of the single crystal pure copper bars are 128.52 MPa, 76.7% and 105.2% IACS, respectively, which show excellent mechanical properties and electrical properties.