Mont Mars (Italian: Monte Mars or Mont Mars locally; from French) at 2,600 m, is the highest peak of the Biellese Alps, north-western Italy.

It is located on the water divide between the Lys Valley (Aosta Valley ) and the Elvo Valley (Province of Biella ).

In the SOIUSA (International Standardized Mountain Subdivision of the Alps) it gives the name to a mountain group called "Catena Tre Vescovi - Mars".

It gives its name to a nearby nature reserve, the Mont Mars Nature Reserve (Italian: Riserva Naturale Mont Mars; French: Réserve naturelle du mont-Mars).

It can be ascended from the south, starting from the Sanctuary of Oropa or, from the North, starting from the Lys Valley. The summit provides a panorama across the plains of the Po Valley and of the Monte Rosa massif.