Two children with Kawasaki disease (KD), a girl 3 yrs. and a boy 2.5 yrs., were described. The children met all criteria for the diagnosis of KD (fever, conjunctivitis, oral changes, extremity changes, rash, lymphadenopathy), and other diseases were excluded. In both children or one of them other clinical and laboratory findings occasionally detected in KD were observed: arthralgia, hepatomegaly and splenomegaly, slight elevation of transaminases and bilirubin level, slight elevation of CSF pleocytosis, sterile pyuria and hematuria. Electrocardiograms revealed sinus tachycardia and transient disturbances of heart repolarization. In both children changes in blood morphology and biochemical disturbances typical for inflammatory processes were noted. Thrombocytosis was seen in the 2nd week of the illness in the child in whom platelet counts were controlled. The child in whom diagnosis of KD was established in the first week of symptoms was treated with acetylsalicylic acid along with an oral penicillin. A child with retrospectively diagnosed KD was treated with antibiotics and corticosteroids. Clinical and laboratory findings of KD resolved in both children within 4-6 weeks without complications from coronary blood vessels.