Lymphangioma is a rare developmental anomaly of the lymphatic system, commonly arising at birth, in infancy, or early childhood. Treatment is rarely curative. We report a case of macrocystic lymphangioma treated with sildenafil in a 16-year-old Filipino child diagnosed clinically, radiologically and histologically. The patient presented with grouped papulovesicles on the left lower extremity, associated with limb length discrepancy, unilateral leg pain and difficulty in ambulation. Given the recurrent course of this condition, even with surgical management, the use of a non-invasive approach such as sildenafil as a potential treatment option for lymphangioma is an important emerging area of study.