A laser joining method and device includes a pressure-applying clamping device, which presses a first and a second workpiece against one another at least after the workpieces have been locally plasticized, and a mask having mask structures, which allow laser light to pass only in the region of the bonding contact faces, wherein at least the workpiece facing the laser source is formed by a three-dimensional molded part, which is not planar at least on the first contour side facing the clamping element and/or on the second contour side facing the second workpiece, and wherein the clamping element, with the bearing side thereof for the first workpiece, is adapted to the first contour side of the first workpiece. The mask structures are created on the bearing side of the clamping element facing the first workpiece or on the second contour side of the first workpiece facing the second workpiece.

A laser welding apparatus is provides that includes: a support member including a heat generation portion which has a size that is limited to correspond to a size of a welding area of a plurality of plastic components and is made from a material that absorbs a laser beam and generates heat, and which generates heat of a temperature that is equal to or greater than a melting temperature of the plastic components; a laser beam irradiation unit for converging a laser beam to be transmitted through the plurality of plastic components, and irradiating the laser beam toward the heat generation portion through the plurality of plastic components; and a welding controller for causing a laser beam to be irradiated at the heat generation portion using the laser beam irradiation unit to thereby cause the heat generation portion to generate heat, and welding abutting faces of a welding area of the plurality of plastic components with heat that is generated.