Introduction: Adenoidectomy is a common procedure in children who have adenoid hypertrophy (AH), but anesthesia risks should be considered. We proposed a novel classification system for adenoids based on their appearance. Additionally, we explored whether the novel classification of adenoids correlates with the response to therapy and thus might be helpful for further treatment recommendations. Methods: We used fiberoptic nasal endoscopy to determine the degree and appearance of AH. Obstructive Sleep Apnea Questionnaire (OSA-18) was used to assess the quality of life of children with AH. The adenoids were divided into three types: edematous type, common type, and fibrous type. In adenoid tissues, the eosinophils were counted. Immunohistochemistry and Western blot were done to determine the expression of CysLTR1, CysLTR2, CGR-α, and CGR-β in different types of adenoids. Results: 70.67% (106/150) of AH patients presented with allergic rhinitis (AR), and of them, 68% (72/106) of adenoids were the edematous type. The expressions of CGR-α, CGR-β, and eosinophil count were higher in the edematous compared with the common and fibrous types. The expression of the leukotriene receptor was similar in all types. Upon montelukast combined with nasal glucocorticoid therapy, improvement of OSA-18 scores and AH grade was significantly compared to montelukast monotherapy for edematous type. There was not any statistically significant difference between the scores upon montelukast combined with nasal glucocorticoid and montelukast monotherapy for common and fibrous type. We observed a positive correlation between eosinophil count in the blood and in the adenoid tissue. Conclusion: AR was the risk factor for the development of edematous AH. All subtypes of AH responded to montelukast, while there was an additional effect of nasal glucocorticoid in the edematous type. A combination therapy of nasal glucocorticoid with leukotriene receptor antagonist can be recommended for AH patients with AR, patients with edematous adenoids, and/or patients with increased eosinophils in blood routine.