OBJECTIVE: Childhood asthma is a multifactorial disease. It is known that anti-inflammatory and antioxidant agents play important roles in the pathogenesis of asthma. However, there are conflicting reports about the roles of antioxidant trace elements such as zinc in asthma. The aim of our study was to investigate the relationship between the serum zinc levels and the severity and control of asthma. MATERIAL AND METHODS: This study enrolled 56 pediatric patients diagnosed with asthma between the ages of 3 to 17 between July 2014 and April 2015, and 26 healthy children. Control levels of asthma were determined based on the Global Initiative for Asthma Guidelines 2014 criteria. Serum zinc levels were studied using the atomic absorption spectroscopy method. Pulmonary function tests were performed on all patients who complied with the spirometry device. RESULTS: Serum zinc levels were not statistically significant different between the asthma and control groups but significantly higher in the partially controlled asthmatic group compared with the full control asthmatic group (p=0.023). There was a statistically significant negative correlation between the control level of asthma and zinc levels (r: -0.437, p = 0.001). The zinc level in the group with FVC below 80% was significantly higher (p = 0.001). There was no significant difference in zinc levels according to asthma severity (p = 0.228). There was no significant correlation between asthma severity and serum zinc level (r = 0.168, p = 0.217). CONCLUSIONS: Serum zinc levels were associated with the level of control of astma in children. Serum zinc levels might be considered as a useful biomarker that supports other parameters to determine the level of asthma control in children.