Graves' disease is the most common autoimmune disease in hyperthyroidism. Sarcoidosis is an inflammatory granulomatous disease of unknown cause. The association of the two diseases has rarely been reported in the literature. We report a new case of newly diagnosed sarcoidosis in a patient followed for Graves' disease. This is an original case of Graves' disease, the course of which was marked by the onset of active sarcoidosis presented as Löfgren's syndrome complicated by hypercalcemia. Given its rarity and the lack of a causal link, the association between Graves' disease and sarcoidosis may be mere coincidence. More studies could allow us to understand more common etiopathogenic mechanisms since both are chronic inflammatory diseases.