Neuromyelitis optica is a rare autoimmune disorder which causes characteristic demyelinating and inflammatory lesions of the CNS situated mostly on the optic nerve and the spinal cord. Lesions can differ in dimensions and positions. This is why neuromyelitis optica can be manifested through a broad spectrum of symptoms such as paraplegia or tetraplegia, symmetric sensorial disorders, sphincter dysfunction, pain and paroxysmal tonic spasms of the trunk and the extremities, unilateral or bilateral ocular pain with loss of visual function, constant hiccups, nausea and others. Etiology of the disease has been unknown for a long time but we know now that one of the reasons for the tissue destruction in the CNS are autoantibodies against AQP4 (bidirectional, osmotic water channels situated mainly on the astrocytes and on ependymal cells in the CNS). Incidence of the disease is higher in Asians, African-Americans, black Africans and in women. Neuromyelitis optica is more common in younger, working population. Diagnosis is based on clinical and paraclinical criteria and on the use of the medical imaging and biochemical techniques. It is important to differentiate neuromyelitis optica from multiple sclerosis. Standard therapy for multiple sclerosis and neuromyelitis optica consists of immunomodulatory and immunosuppressive drugs. In spite of better understanding of the pathogenesis and molecular background of the disease, there are still various unknown facts which make this disease interesting for further researching.