A semiconductor laser excitation solid-state laser comprises: a planar waveguide-type solid-state laser element which is disposed on a solid-state laser substrate; an LD array; and a sub-mount substrate on which joining layers of two different thicknesses are formed on the same plane; wherein the planar waveguide-type solid-state laser element is joined to the sub-mount substrate on the surface on the opposite side of a surface on which the solid-state laser substrate is mounted, via a joining layer of one of the thicknesses out of the joining layers of the two different thicknesses, and the LD array is joined to the sub-mount substrate on the surface on a light-emitting layer side, via another joining layer of the other thickness out of the joining layers of the two different thicknesses.