Asthma is a chronic inflammatory disorder of the lower airways, characterized clinically by reversible airway obstruction and bronchial hyper-responsiveness (BHR). Tryptase is a neutral serine protease and is the most abundant mediator stored in mast cell granules. The release of tryptase from the secretory granules is a characteristic feature of mast cell degranulation in allergic diseases. This study aims to evaluate the difference between serum tryptase levels and asthma severity in the Sulaimani governorate. Five milliliters of venous blood were obtained from 85 healthy control and 85 asthmatic patients were subdivided into three groups; controlled asthma (n = 25), partly controlled asthma (n = 30) and uncontrolled asthma (n = 30). Serum tryptase level was analyzed by using sandwich ELISA. There was a significant difference among the study groups, with highest serum tryptase levels in the uncontrolled asthma group (7.68 ± 0.65 ng/dl) and lowest levels in the controlled asthma group (4.4 ± 0.15 ng/dl). Serum tryptase levels increase significantly with age. There was a significant difference between ex-smokers and never-smokers among asthmatic subjects. No significance in serum tryptase levels was found between males and females and between asthmatic subjects with negative and positive family history of asthma. Serum tryptase levels in uncontrolled asthma were significantly higher than in controlled asthma. Serum tryptase levels are elevated with age and also in ex-smoker asthmatic subjects. However, there was no significant difference in the levels of serum tryptase according to gender and family history of asthma.