Asthma is a disease of conducting airways and there is a general agreement that airway inflammation is likely critical components of asthma pathogenesis. Omega-3 fatty acids competitively inhibit the formation of prostaglandins and leukotrienes derived from arachidonic acid. This study was design to identify the effect of omega-3- fatty acids on respiratory symptoms, airway function and numerous cytokines including IFN-γ, IL-1β, IL-2, IL-4, IL-5, IL- 6, IL-9, IL-10, IL-12, IL-13, IL-17A, IL-22 and TNF-α in patients with persistent asthma. Fifty families who has a child with proven persistent asthma registered to this study. After obtaining informed consent from the patients’ parents, demographics characteristics were collected. The patients were scheduled to take 1000 mg omega-3 fish oil (Best Formulations Inc., LA, CA, USA) in the form of soft gel capsules daily for consecutive three months. Patients with a history of allergy to seafood, those under treatment with anti- interleukin and those develop side effects such as nausea and vomiting were excluded. At the beginning of the study and the end of three months after intervention phase, the patients were assessed for subjective symptoms; pulmonary function test and measuring cytokines. Each child is serving as their own control for results. Recruitment start date will be during winter 2014.