The etiological mechanism of asthma in children is complex and has multiple causes, the most common and important of which is allergy, so most asthma is allergic. In children diagnosed with asthma, further allergen testing should be performed to find out whether the child with asthma has allergies, that is, whether his asthma is allergic, to which allergens he is allergic, and to what extent he is allergic. After the type and degree of allergens are clarified through allergen testing, measures can be taken to avoid exposure to allergens for the purpose of preventing asthma attacks. For example, mites are the most common allergens. By cleaning indoor hygiene and using dust mite bed covers, exposure to mites can be reduced and acute asthma attacks can be reduced; children with seasonal pollen allergy can avoid exposure to allergens or stay away from these allergens by wearing masks during pollen season. Some studies have shown that some children with well-defined allergens can reduce asthma attacks if they avoid allergens altogether and do not use any medications. In addition, if a child with asthma has a moderate/severe allergy to an allergen or is predominantly allergic to an allergen, desensitization to that allergen can be used as “allopathic treatment” to reduce the clinical symptoms caused by the allergy or even to “cure” it. Therefore, allergen detection is essential for the management of asthma. Therefore, allergen detection is very important for the definite diagnosis and long-term prevention of asthma. Only when the nature of asthma and allergies are clearly defined can effective measures be taken to avoid exposure to allergens and to determine whether immunotherapy is possible.