To investigate the correlation between serum galectin 3 (Gal-3), tryptase, 25-hydroxyvitamin D3[25 (OH)D3]and lung function and quality of life in children with bronchial asthma (asthma for short).Methods: A total of 136 children with asthma who were admitted to our hospital from February 2018 to March 2021 were selected as the study group, after pulmonary function test, they were divided into mild group with 63 cases, moderate group with 41 cases and severe group with 32 cases according to the severity of the disease. Another 40 healthy children during the same period were taken as the control group. The serum Gal-3, tryptase and 25(OH)D3 levels were detected and compared among groups. The lung function indexes of asthmatic children in each group were com-pared, and the Pediatric Asthma Quality of Life Questionnaire (PAQLQ) was used to evaluate the quality of life of asthmatic children in each group. The relationship between the serum Gal-3, tryptase, 25(OH) 2D3 levels and lung function and quality of life were analyzed by Pearson correlation. Results: The levels of serum Gal-3 and tryptase in the study group were higher than those in the control group, and gradually increased in the mild group, moderate group and severe group; The levels of serum 25 （OH）D3were lower than those in the control group, and gradually decreased in the mild group, moderate group and severe group (P＜0.05). The percentage of forced expiratory volume in the first second (FEV1%pred), the percentage of respiratory peak flow rate in the predicted value (PEF%pred), forced expiratory volume in the first second/forced vital capacity (FEV1 /FVC) and PAQLQ scores in the moderate and severe groups were lower than those in the mild group, and the severe group was lower than those in the moderate group, the differences were statistically significant(P＜0.05). Pearson correlation analysis showed that the serum Gal-3 and tryptase levels were negatively correlated with lung function indexes and PAQLQ scores, while the serum 25 (OH) D3 level was positively correlated with lung function indexes and PAQLQ scores(all P<0.05).Conclusion: Serum Gal-3, tryptase and 25 (OH) D3 levels are closely related to lung function and quality of life in children with asthma, and which may be a reliable index for assessing the disease condition and quality of life. [ABSTRACT FROM AUTHOR]