Abstract: A correction mouthpiece (1) for an ideal smile, by which a shape of an upper labium can be corrected so as to give an ideal smile, includes an upper jaw mouthpiece part (4) having an upper tooth row fitting portion (2) to be fitted to an upper tooth row of a wearer to be corrected and an upper jaw contact portion (3) to be brought into contact with an upper jaw thereof. The upper tooth row fitting portion (2) of the upper jaw mouthpiece part (4) has a front tooth row part fitting portion (2a) having an upper anterior portion integrally provided with an upper labium fitting part (5) to be fitted along the upper labium of the wearer to be corrected. The upper labium fitting part (5) has a concave surface (5a) of a concave surface shape that corrects the upper labium of the wearer to be corrected to have an ideal upper labium shape.