Schizophrenia is one of the most severe and disabling psychiatric disease that affects about 1 % of the adult worldwide population. Aetiology of schizophrenia is still unknown but genetic and environmental factors are suspected to play a major role in its onset. Recent epidemiologic studies indicate that infectious agents may contribute to some cases of schizophrenia. In particular, several epidemiological, behavioural and neurochemical studies suggested the existence of an association between schizophrenia and past history of primo-infection by the Toxoplasma gondii. However, they are some limitations for this hypothesis among which the lack of correlation between the geographic distribution of both diseases and of direct evidence for the presence of the parasite in schizophrenic patients. Nevertheless the identification of physiopathological mechanisms related to the parasite could provide a better comprehension to the outcome of schizophrenia. Studies on the link between toxoplasmosis and schizophrenia may provide interesting data for the diagnosis and the development of new treatments for this disorder.