Objective    To explore the relationship between serum levels of tumor necrosis factor-α(TNF-α), interleukin-4(IL-4), eosinophil cationic protein (ECP) and the degree of adenoid vegetation and body mass index(BMI) in children with adenoid vegetation. Methods    87 cases of children with adenoid vegetation confirmed by X-ray imaging of nasopharynx (experimental group) and 49 normal subjects (control group) were enrolled. The height, weight and body mass index (BMI)of 136 children were documented. The size of vegetation was indicated by the ratio between the adenoid and nasopharyngeal diameter(A/N). With fasting venous blood, the serum levels of TNF-α、 IL-4  were determined by enzyme-linked immunosorbent assay kit (ELISA) and serum ECP levels were measured by Pharmacia CAP System ECP FEIA. The relationship between the degrees of adenoid vegetation and BMI and the levels of TNF-α、 IL-4、 ECP were analyzed by  SPASS 17.0. Results    The serum levels of TNF-α、 IL-4 in experimental group were higher than those in controls (P<0.05), but the levels of ECP were similar in the two groups (P>0.05). Levels of TNF-α and the degree of adenoid vegetation were positively correlated (mild degree: r=0.98， P<0.05； mediate degree： r=0.92, P<0.05； severe degree： r=0.9,  P<0.05); Levels of IL-4, but not ECP,  were also corelated positively with the degree of adenoid vegetation (mild degree: r=0.95， P<0.05； mediate degree：r=0.94， P<0.05；severe degree： r=0.99, P<0.05) . Conclusion    The serum levels of TNF-α、 IL-4 in children with adenoid vegetation increase to some extent, and their levels are corelated positively with the degree of adenoid vegetation as reflected by A/N ratio.，but not with BMI. However, the serum levels of ECP show no obvious correlation.