The invention relates to a splicing device and method of crystal bars with equal length or square crystal ingots with equal length. The splicing device contains a splicing mechanism and a matched sucking tool; the set screws of a bearing centring barrel are used to fix constant diameter short crystal bars or equilateral square ingots; a concentricity-determining device is used to ensure that the concentricity of the four crystal bars or square ingots which are overlaid; the four crystallization symmetric ridges of the four crystal bars are aligned from bottom to top or all the angles of the four square ingots are aligned from bottom to top; a straight line is drawn on the outer surface of each short crystal bar or square ingot to be used as secondary butt-joint line, the sucking tool is used to lift the second, third and four crystal bars or square ingots in turn, adhesive is coated, aligning is performed according to the secondary butt-joint lines, and the crystal bars or square ingots are fixed and spliced. By adopting the device and method of the invention, the splicing time is short, the sliced crystal bar or ingot has good concentricity, the four crystallization symmetric ridges or the angles of the square ingots are easy to align and the standardized and mass production is easy to realize.