Asthma is one of the most common allergic diseases in children. As a result of the advances in immunology and the studies of BAL and lung biopsy, the definition of asthma has been changed as a 'chronic inflammatory disorder of the airways'. Therefore pharmacologic therapy of asthma is focused on the control of allergic inflammation. According to its purpose, the asthma medication could be classified into two groups, that is, quick-relief agents and long-term control agents. Quick-relief agents give a prompt relief of acute symptoms (coughing, wheezing, difficulty of breathing, and chest tightness) and prevent exercise-induced bronchospasm. Short-acting inhaled β2-agonist is at present the most effective quick-relief agent. Long-term control agents are taken daily and chronically (for a long period of time) to maintain the control of persistent asthma and to prevent exacerbations, and include inhaled corticosteroid, cromolyn sodium, and others. A stepwise approach is recommended for treating a child with asthma to attain and maintain asthma control. Medications should be carefully chosen according to the severity of asthma and age of children.