OBJECTIVE: To study the possible relationship between coronary artery lesions and fibrinogen Bβ-148 C/T polymorphism in children with Kawasaki disease. METHODS: Fast blood samples were taken from 36 children with Kawasaki disease (21 had coronary artery lesions) and 49 age-and gender-matched healthy children (control group). Plasma levels and molecular reactivity of fibrinogen were measured with Assist Plasma Fibrinogen Activity Assay System. Polymerize chain reaction and restriction enzyme digestion were used to detect the genotypes of fibrinogen Bβ-148C/T gene polymorphism. RESULTS: The plasma fibrinogen levels in patients with coronary artery lesions were significantly higher than those in patients without coronary artery lesions and in the control group. T allele frequency in patients with Kawasaki disease was significantly higher than that in the control group. The patients with coronary artery lesions had more increased T allele frequency compared with the patients without coronary artery lesions. CONCLUSIONS: Plasma fibrinogen levels and fibrinogen Bβ-148C/T polymorphism are associated with coronary artery lesions in children with Kawasaki disease.［Chin J Contemp Pediatr, 2010, 12 (7):518-520］