Children with Kawasaki disease (n = 82), treated with intravenous immune globulin (IVIG) at a high dose, were classified as IVIG-responsive (defervescence within 5 days of starting IVIG, n = 69) or IVIG-non-responsive (consistent fever over a 6-day period since starting IVIG, n = 13). One patient in the IVIG-responsive group had a coronary artery abnormality during the acute phase (1. 4%) versus 5 in the IVIG-non-responsive group (38.5%). Age, duration of fever before the initiation of IVIG therapy, and laboratory data obtained on admission were tested by the Mann-Whitney U test. Serum levels of C-reactive protein, total bilirubin, lactate dehydrogenase, and gamma-glutamyltranspeptidase were significantly higher (P =.002, P <.001, P <.034, and P <.038, respectively), and the hemoglobin value was significantly lower (P =.025) in patients in the non-responsive group. A multivariate analysis showed that serum levels of C-reactive protein (P =.006), lactate dehydrogenase (P =. 035), and total bilirubin (P =.046) on admission were independent correlates of the success of IVIG therapy. By defining the predictive values, patients with a C-reactive protein level >10 mg/dL, LDH level >590 IU/L, and/or hemoglobin value <10 g/dL are considered non-responsive to IVIG. Additional therapy at an early stage of the disease should be considered for patients who are predicted to be IVIG-non-responsive.