Objective To retrospectively analyze the allergen characteristics and the onset season of allergic rhinitis (AR) patients in Shanghai, China. Methods From Jan. 1, 2015 to Dec. 31, 2017, 1 570 suspected AR patients were selected from the Department of Otolaryngology/Head and Neck Surgery, Changzheng Hospital, Naval Medical University (Second Military Medical University). One milliliter of serum was extracted from each patient and the specific immunoglobulin E (IgE) levels of 22 kinds of allergens and total IgE levels were detected using allergen specific IgE antibody detection kit (immunoblotting method). The AR patients were divided into 5-16, 17-39, 40-64 and ≥ 65 years old groups, and the positive rates of allergens were compared. The number of AR patients with one or more positive allergens was recorded every month, and the seasonal distribution of positive allergen was analyzed. Results Of the 1 570 suspected AR patients, 143 (9.1%) had elevated serum total IgE, and 1 182 (75.3%) had one or more positive allergens, including 491 (41.5%) with single positive allergen and 691 (58.5%) with two or more positive allergens. Among the 22 kinds of allergens, dust mites (including Dermatophagoides pteronyssinus and Dermatophagoides farinae) were the most common allergens (715 cases, 60.5%), followed by penicillin (239 cases, 20.2%) and Chinese parasol (167 cases, 14.1%). Among the 1 182 AR patients, 17-39 years old was the highest proportion (61.0%, 721 cases). The positive rate of dust mites in the 5-16 years old group was significantly higher than those in the 17-39, 40-64 and ≥ 65 years old groups (all P<0.05). The prevalence peaks of AR were in Apr., May, Jun., Aug., Sep., Oct. and Nov.; and the numbers of AR patients with one or more positive allergens were 175±21, 156±16, 259±31, 172±15, 176±14, 164±4 and 204±32, respectively, which were significantly higher than the average value (97±42) of 36 months from Jan. 1, 2015 to Dec. 31, 2017 (all P<0.05). The positive detection time of dust mites was mainly in May, Jun., Jul., Aug., Sep. and Nov.; and the numbers of dust mite positive AR patients were 64±11, 113±21, 68±18, 76±15, 70±11 and 89±21, respectively, which were significantly higher than the average value (52±32) of the 36 months (all P<0.05). Conclusion Dust mites are the most common and main allergens of AR patients in Shanghai, China. The proportion is high in AR patients aged 17-39 years old, and the prevalence peaks are from Apr. to Jun. and from Aug. to Nov..