Morbihan syndrome (MS) is characterized by solid facial edema, usually related to rosacea or acne vulgaris. The facial edema deforms the patient’s features, can impair peripheral vision, and affects quality of life. Its pathophysiology remains unclear. The disease usually has a slow and chronic course. MS most commonly affects middle-aged Caucasian men with rosacea and is rare in people below 20 years of age. MS is a diagnosis of exclusion. There is no standard treatment for MS, though systemic isotretinoin and antihistamines are mainly used. We present the case of an adolescent girl with MS nonresponding to 19 months of isotretinoin treatment with add-on antihistamines. Therapy with monthly administration of omalizumab (anti-IgE) for 6 months was an effective therapeutic option, improving the quality of life. Our case is the second description of omalizumab use in Morbihan syndrome, the first in an adolescent.