The neurological manifestations of three adult cases with acquired toxoplasmosis appearing like a focal lesion, multiple sclerosis and with symptoms indicating a cerebellar lesion are reported. The discussion with respect to the literature shows the following results: 1. The diagnosis of mono- and oligosymptomatic toxoplasmosis with neurological symptoms is only approximate after the introduction of the indirect immunofluorescence test too. 2. The toxoplasmosis of the nervous system in the adult is not characterized by a special syndrome like the connatale form. In contrary, it often is mimicking many well known neurological or psychiatric syndromes. 3. There may be an exacerbation of a latent infection in cause of immunosuppressive therapy or radiation of malignancy or after transplantations. 4. Treatment with the combination of pyrimethamine and sulfonamids today is handled less in spite of the possible complications and of doubtful serological results, because an early diagnosis and onset of treatment is important for a good restitution.