Background: Adipokines have been claimed for the link between obesity and asthma. The aim of the present study was to evaluate the roles of leptin and adiponectin in children with asthma and/or obesity and their effect on pulmonary functions. Methods: Obese (n = 71) and lean asthmatics (n = 72), obese non-asthmatics (n = 46), and lean healthy children (n = 49) were included in the study. Serum leptin and adiponectin levels were compared according to groups and sex. Results: Mean leptin levels of obese asthmatics were higher than those of lean asthmatics (13.1 -9.1 vs. 3.7 -4.4; p < 0.001). Serum adiponectin levels of lean asthmatics (16 -7.1) were significantly higher than those of obese asthmatics (12.1 -6.9; p < 0.001) and of their lean healthy (13.2 -5.9; p < 0.05) counterparts. In obese asthmatics, adiponectin levels were positively correlated with the forced expiratory volume in one second (FEV 1 )/forced vital capacity (FVC) ratio, and serum leptin levels were inversely correlated with forced expiratory flow ). Leptin/adiponectin ratio was inversely correlated with FEV 1 /FVC ratio in lean and obese asthmatic patients. Conclusions: The present findings suggest that adiponectin may have protective disease modifying effect(s) in asthmatic children. Anti-inflammatory mechanisms regarding adiponectin may work better in girls than in boys.