Introduction: one of the hypotheses about the relationship between asthma (A) and obesity is that the visceral adipose tissue (VAT) produces pro-inflammatory cytokines enhancing inflammation in the bronchi. However, generally used BMI does not reflect the content of VAT in the body. Leptin is pro-inflammatory cytokine; its involvement in A pathogenesis is still unclear. Objective: to evaluate serum leptin levels, measure the VAT and subcutaneous adipose tissue (SAT) areas by CT at the level L4-L5 and explore their correlations with spirometry parameters in overweight and obese A patients (pts). Material and Methods: we examined 78 pts with A (68 women, 10 men; 19-76 yo). The 1st group included 25 pts (BMI 18.5-24.9 kg/m2), the 2nd – 21 pts (BMI 25-29.9 kg/m2), the 3rd – 32 pts (BMI≥30 kg/m2). Results: pts in the 2nd and the 3rd groups had a more severe course of A vs group 1 (p=0.02): moderate and severe A were almost twice often in pts with BMI≥25 kg/m2. Leptin levels in the 2nd and the 3rd groups (39.6[22.9;59.4], 79.8[48.3;105.1] ng/ml, respectively) were significantly higher than in the 1st group (13.4[4.9;34.7] ng/ml, p=0.002). The VAT and SAT areas were 70.7[39.3;97.2] and 169.7[133.9;226.2]cm2, 121.0[92.7;139.1] and 291.6[237.8;334.0]cm2, 179.3[128.9;217.5] and 470.7[394.4;549.5] cm2 in the 1st, 2nd, 3rd groups, respectively (p Conclusion: elevated leptin levels and increased VAT areas in overweight and obese A pts apparently contribute to a more severe course of A and play an important role in this comorbidity.