The Breithorn (4164 m, from German: broad horn) is a mountain located in the Pennine Alps on the border between Switzerland (Valais) and Italy (Aosta Valley).

It is also the name of several other mountains:

Switzerland Breithorn (Lauterbrunnen) (3780 m), part of the Bernese Alps, between the Lauterbrunnental and the Lötschental Breithorn (Blatten) (3785 m), part of the Bernese Alps, between the Lötschental and the major valley of Valais, belongs to the municipality of Blatten Kleines Breithorn (3656 m), 300 m south of Breithorn (Blatten) Breithorn (Simplon) (3437 m) Breithorn (St. Niklaus) (3178 m) Breithorn (Grengiols) (2599 m), part of the Lepontine Alps and the municipality of Grengiols, in the district of Östlich Raron, Valais Austria Breithorn (Steinernes Meer) in the Steinernes Meer, Nördliche Kalkalpen Breithorn (Loferer Steinberge) in the Loferer Steinberge, Nördliche Kalkalpen

See also Broad Peak (named after the Breithorn)