Oral H1-antihistamines are one of the most commonly prescribed drug categories in the treatment of allergic diseases in children. However, its rational application still lacks sufficient evidence and pharmaceutical guidance, making its clinical use risky. Based on the best available evidence, expert experience, and the willingness of patients' families, the guideline development panel developed this guideline, using the grading of recommendations assessment, development and evaluation (GRADE) approach. The guidelines developed 19 recommendations in 8 domains, covering the therapeutic status of oral H1-antihistamines in pediatric allergic diseases, age range, dose, duration of treatment, adjustment in the presence of hepatic and renal insufficiency, drug interactions, adverse effects and adherence. As a result, this guideline helped to standardize and guide the rational use of oral H1-antihistamines in pediatric allergic diseases.