Diagnosis of cerebral ring enhancing lesions on CT or MRI studies is quite frequent. Their differential diagnosis is diverse, including infectious, tumoral, demyelinating and vascular diseases. Information provided by cranial imaging, notably by the different sequences on magnetic resonance imaging (TI, T2, FLAIR and diffusion-weight imaging) is helpful to differentiate between the different causes. The aim of this article is to discuss some of infection which may occur in our region and presenting as a cerebral lesion with annular enhancement. We consider infection in immunocompetent and immunocompromised patient.