The number of cases of Kawasaki disease increases in Japan. The aetiology is still unknown but epidemiological studies suggest an infectious aetiology in spite that no specific microorganism has been implicated; it must be, probably present a hereditary predisposition connected with HLA subtypes. Many investigators reported an increase in the antibody level against several agents, among which bacteria and virus. Recently they found that aberrant regulation of T- and B-cells functions was associated with initiation of such antibody production, that in the majority of cases is self-limiting. The effectiveness of high- and low-doses of salicylates, given always associated with steroids, only up to fifteen days of illness, and Intravenous Gamma Globulin (IVGG), is also discussed.