A laser welding jig of a triangular titanium alloy covering and skeleton weld assembly relates to a laser welding jig. The invention aims to solve the existing problem that the front tip of the triangular titanium alloy covering and skeleton weld assembly upwarps and deforms in laser welding. In the laser welding jig, a first positioning plate, a second positioning plate and a guide base are fixedly connected with a bottom plate; the first positioning plate and the second positioning plate are perpendicular to each other; a first compression quick change chuck is fixed on the guide base, the first compression quick change chuck is connected with a first pressure plate; two guide sleeves are fixedly connected with the guide base, each guide post is fixedly connected with the first pressureplate; a reinforcing frame is fixed on the first positioning plate, a second pressure plate is arranged in the reinforcing frame; the first pressure plate, the second pressure plate, the first positioning plate and the second positioning plate constitute a triangle with the same shape with the triangular titanium alloy covering and skeleton weld assembly; a second compression quick change chuck is fixed on the outside surface of the first positioning plate; and a third compression quick change chuck is fixed on the outside surface of the second positioning plate. The laser welding jig in the invention is used for the laser welding of the triangular titanium alloy covering and skeleton weld assembly.