We report two cases with diagnosis of progressive ossifying fibrodysplasia (FOP) at the “Eugenio Espejo” Specialty Hospital. The FOP is a rare autosomal dominant disease. In most of the patients is due to a mutation in families not affected previously. It’s characterized by progressive ossification of connective tissue, aponeurosis, fascia, ligaments, tendons and skeletal muscle. The early diagnosis improves the prognosis and the quality of life.