The invention belongs to the technical field of materials, and provides a directional interconnection method for Cu6Sn5-base single-crystal lead-free solder joints for high-temperature packaging. The method comprises the steps of firstly, preparation of a Cu6Sn5-base single-crystal block body, secondly, cutting of the Cu6Sn5-base single-crystal block body, thirdly, surface pretreatment of a Cu-base welding disc, and fourthly, interconnection of Cu6Sn5-base single-crystal welding blocks. The elasticity modulus of the Cu6Sn5-base single-crystal lead-free interconnected solder joints prepared with the method is 235% of that of common Sn-base brazing filler metal, the conductivity of the Cu6Sn5-base single-crystal lead-free interconnected solder joints is 52.4% that of the Sn-base brazing filler metal, and the heat conductivity of the Cu6Sn5-base single-crystal lead-free interconnected solder joints is 57.8% that of the Sn-base brazing filler metal. The method has the beneficial effects of being low in cost, resistant to high temperature, high in reliability of interconnection of the solder joints and a Cu-base welding disc, high in creep-resistance, and capable of being used for a long time under the severe condition. The method has the beneficial effects of being simple in working principle, low in cost, rapid in single-crystal preparation and high in quality.