This study combines double-sided laser and laser swing welding technologies to realize a double-sided laser swing welding of 2195-T87 aluminum-lithium alloy T-joint. Double-sided laser swing welding with circular swing method is used to obtain 2195-T87 aluminum-lithium alloy T-joint with firm surface forming and low porosity. The porosity rate is reduced from 1.89% to 0.52%. Compared with conventional double-sided laser welding, double-sided laser swing welding can significantly refine the equiaxed crystal area in the middle of the weld by beam swinging and stirring the molten pool, and significantly reduce the size of the equiaxed, fine-crystal area to enhance the joint’s load-bearing capacity. The average diameter of the equiaxed crystal in the middle is reduced from 21 to 13 μm, while the average diameter of the equiaxed, fine-crystal region is reduced from 44 to 23 μm. The obtained joints have maximum axial and transverse tensile strengths of 267 and 420 MPa, respectively. Compared with nonswing welding, they increased by 123 and 95 MPa, respectively, reaching 45% and 70% of the base metal strength. Our study shows that double-sided laser swing welding can design 2195-T87 aluminum-lithium alloy joints of better surface forming, lower porosity, and greater strength.