Abstract: Objective　To summarize the clinical characteristics, follow-up and prognosis of Kawasaki disease (KD) in infants under 3 months. Method　The clinical data of infants under 3 months diagnosed with KD during January 2009 to December 2013 were analyzed retrospectively. Results　In a total of 1504 cases diagnosed with KD during during the study period, there were 40 (2.66%) infants under 3 months (30 males and 10 females). Except for fever, the frequencies of the other 5 main clinical manifestations were less than 50%. Laboratory tests suggested inflammatory reactions, thrombocytosis, anemia, and so on. Coronary artery disease was found in 32 cases (80%), including 24 cases of coronary artery dilatation, 8 cases of coronary artery aneurysm and 3 cases of coronary giant aneurysm. By the end of the follow-up period, there were no myocardial ischemia, myocardial infarction and death in all the patients; coronary artery diameter was normal in 37 cases (92.5%); 3 cases of giant coronary artery aneurysm still had coronary artery aneurysm and thrombosis. Conclusion　The clinical manifestations of KD in little infants were atypical, the incidence of coronary artery disease is high, and color doppler echocardiography should be performed in time.