Adenoid hypertrophy is one of the most common causes of upper airway obstruction in childhood. Chronic inflammation around the adenoid tissue is thought to play an important role in adenoid hypertrophy. Allergic rhinitis is among these chronic inflammatory processes. Twenty-five-month-old male patient presented to otorhinolaryngology clinic with complaints of nasal obstruction, snoring, sleeping with mouth open at night and occasional shortness of breath while sleeping. His examination did not show any pathology other than pallor in the nasal mucosa. Adenoid vegetation/nasopharynx ratio was found to be 80% in the examination made by using fiberoptic nasopharyngolaryngoscope. Tonsillar grade was 1-2 hypertrophic in oropharyngeal examination. In the skin prick test, the patient was found to have grass pollen and tree pollen sensitivity. Nasal steroid and antihistaminic therapies were started. After treatment, the patient’s adenoid vegetation/nasopharynx ratio and complaints were found to decrease significantly.