Neurocryptococcosis was a rare nervous system infection. With the rising number of patients with AIDS it became a very frequent disease. This infection is supposed to infect patients with some kind of immunodeficiency and the CSF alterations often simulate tuberculous meningitis. The purpose of this research was to compare the CSF changes in AIDS and non-AIDS patients with meningoencephalitis caused by Cr. neoformans. There were analysed 41 CSF samples from non-AIDS patients with neurocryptococcosis and 23 CSF samples from AIDS patients with neurocryptococcosis. The results of this research allowed to conclude that the inflammatory changes in the CSF from AIDS patients showed a lower intensity compared to those non-AIDS patients. These results showed as well, that the CSF samples from non-AIDS patients always revealed some changes besides the yeast cells. In some samples of AIDS patients, however the unique change was the presence of the yeast. It was demonstrated also, that the presence of Cr. neoformans in CSF, not accompanied by any other change, may suggest that is a patient with AIDS. In non-AIDS patients CSF alterations often simulates tuberculous meningitis. However these alterations were rare in AIDS patients. The yeast cells were more numerous in CSF samples from AIDS patients than in those from non-AIDS patients.