Background: Cystic fibrosis (CF) is a pulmonary disease leading to the destruction of lung tissue caused by repeated infection with typical pathogens like Pseudomonas aeruginosa (PA). Different T cell subsets, an imbalance in cytokine levels and a protease-antiprotease imbalance play a role. This study aimed to investigate the potential influence of alpha-1-antitrypsin (AAT) on various cytokines in CF. Methods: Levels of AAT and T-helper-cell-associated cytokines (GM-CSF, IL2, IL6, IL10, IL12p70, IL13, IL17, IL21, IL23, TGFβ,) have been measured in supernatant of induced sputum of CF patients and compared between patients who tested positive for PA (PA-positive) and those who tested negative (PA-negative). Results: Measurements have been performed for 17 CF patients (mean age 14.16 (±4.22) years, 9 female/8 male, 9 PA-positive, 8 PA-negative). AAT correlates with Treg-associated cytokines IL10 and IL12p70 (p < 0.05 and p < 0.05 respectively), a borderline significance with TGFβ exists (p = 0.06). AAT and Treg-associated cytokines IL10, IL12p70 and TGFβ are lower in PA-positive CF patients compared to PA-negative CF patients (24.78 vs. 41.1 pg/ml, p = 0.69, 0.14 vs. 0.26 ng/ml, p = 0.68, 0.17 vs. 0.41 ng/ml, p = 0.32 and 109.32 vs. 227.96 ng/ml, p = 0.85, respectively). GM-CSF significantly correlates with AAT (r=0.75; p<0.05) and Treg-associated cytokines IL2, IL10, IL12p70, IL13 and TGFβ (r=0.93; p<0.001, r=0.9; p<0.01, r=0.73; p<0.05, r=0.97; p<0.001 and r=0.88; p<0.01, respectively). Conclusion: In this cross-sectional study AAT correlates with Treg-associated cytokines. Higher levels of AAT are observed in PA-negative CF patients.