Objective To analyze the levels of serum lipocalin 2 (LCN2) and syndecan 1 (SDC⁃1) in children with bronchial asthma, and to explore the relation of the two as above with disease severity and asthma control level, as well as to explore the diagnostic value on children with bronchial asthma. Methods A total of 112 children with bronchial asthma were enrolled into asthma group, and 104 healthy children were into normal group. According to disease severity, children of the asthma group were further assigned to mild intermittent group (36 cases), mild persistence group (25 cases), moderate persistence group (32 cases), or severe persistence group (19 cases). Serum LCN2 and SDC⁃1 levels were compared between the asthma group and the normal group, and between children with different disease severity in the asthma group. The correlation of serum LCN2 and SDC⁃1 in children with bronchial asthma, and the correlations of the aforementioned indices with forced expiratory volume in one second (FEV1), FEV1 to force vital capacity (FVC) ratio (FEV1/FVC) value, Childhood Asthma Control Test (C⁃ACT) score were analyzed. Drawing receiver operating characteristic (ROC) curve to analyze the diagnostic value of serum LCN2 and SDC⁃1 levels in children with bronchial asthma. Results Compared with the normal group, the asthma group exhibited elevated serum LCN2 and SDC⁃1 levels (P<0.05). Serum LCN2 and SDC⁃1 levels in children with bronchial asthma were elevated successively in the mild intermittent group, the mild persistence group, the moderate persistence group, and the severe persistence group (P<0.05). Serum LCN2 level positively correlated with serum SDC⁃1 level in children with bronchial asthma, and serum LCN2 and SDC⁃1 levels negatively correlated with FEV1, FEV1/FVC value, and C⁃ACT score, respectively (P<0.05). Area under the curve (AUC) of serum LCN2 and SDC⁃1 levels for jointly diagnosing children with bronchial asthma was 0.881, which was larger than AUC of serum LCN2 and SDC⁃1 levels for simple diagnosis (AUC of 0.778 and 0.768, respectively, P<0.05). Conclusion Serum LCN2 and SDC⁃1 levels are elevated in children with bronchial asthma, and are related to disease severity and asthma control level. Serum LCN2 and SDC⁃1 levels can be regarded as biomarkers for adjuvant diagnosis of children with bronchial asthma, and the combined diagnosis of the two exhibits higher efficiency.