Among the different targets affected by immunodeficiency, skin is at the first line. Infections are the most frequent causes of cutaneous manifestations in immunocompromised subjects. They are primitive or secondary cutaneous infections occurring during disseminated disease. Skin manifestations may reveal the systemic disease. Primary or secondary bacterial, viral, fungic, and parasitic mucocutaneous diseases are often atypical, extensive and frequently follow chronical course. These peculiar presentations makes diagnosis difficult. The knowledge of the clinical pleomorphism of skin infections in immunocompromised subjects is essential. All doubtfull lesions must lead to histological and microbiological study. Diagnosis delay may increase the risk of dissemination resulting in morbidity and mortality.