Clinical features of Lucio’s phenomenon (LP), shows a nectorizing erythema, may mimicking Erythema Nodosum leprosum with vasculonecrotic. A 46 years old man presented with diagnosis lepromatous leprosy with Lucio’s phenomenon and diferential diagnosis borderline lepromatous (BL) with vasculonecrotic erithema nodosum leprosum. The patients complained there were painless ulcers on his lower limbs and scrotum, with surrounded by purpuric patches which subsequently became gangrenes and ulcerated for 3 weeks. There was numbness of both hands and feet, the eyelashes, eyebrows baldness since 5 years ago. Patient never got the treatment before. Bacteriological examination showed bacterial index 6+ Histopathology: there were Flattened epidermis by narrow grenz zone, and lymphocyte in perivascular with macrophage. There was endothelial proliferation of capiller. Fite faraco stain showed macrophage infiltration around the perivasculer, with colonization of the endothelial cell by acid fast bacilli and epidermal necrosis and diagnosis as Lepromatous leprosy with Lucio phenomenon. This patient is given adult multiple drug therapy (MDT) therapy, methylprednisolone, neurotrophic vitamins. Lucio’s phenomenon most commonly affects patients with untreated leprosy. Clinically, it may be difficult to differentiate Lucio phenomenon from Erythema nodosum leprosum with vasculonecrotic. In this case, the histopathological examination were colonization of endothelial cell by acid fast bacilli, epidermal necrosis and endothelial proliferation of the vessel.