Objective:To evaluate the efficacy of specific sublingual immunotherapy (SLIT) with Dermatophagoides farinae drops on preschool and school age children with allergic rhinitis.Method:Fifty preschool children (≤6 year), and 52 school age children (> 6 year), who suffered from dust mite induced allergic rhinitis, were randomly divided into subingual immunotherapy (SLIT) + drug group and drug group. SLIT + drug group was treated with a standardized subingual immunotherapy drops of Dermatophagoides farinae and combined with symptomatic therapy, drug group was treated with mometasone furoate nasal spray and dseloratdine tablets as symptomatic treatment. These children were followed up for 2 years with one visit in every 3 months. Symptom scores and medication scores were record at each visit. Comprehensive evaluation of symptom, medication, and patients' degree of satisfaction were used.Result:Two years after SLIT finished, symptom scores (SLIT + drug group: 1.13±1.05; drug group: 4.68±3.09), medication scores (SLIT + drug group: 0.07±0.04; drug group: 0.36±0.25) of SLIT+drug group were significantly lower than those in drug group respectively, all P< 0.01. The subjective assessment of patient' symptom, medication, and treatment satisfaction in SLIT+drug group was significantly lower than those in drug group. Subjective assessment symptoms, medication, and treatment satisfaction in preschool group was the same as in school age group. After SLIT ended for 2 years, subjective assessment and treatment satisfaction in the school age group was better than those in preschool group in medication score.Conclusion:SLIT demonstrated clinical improvement in children of different ages during 2 years treatment. the symptom scores, medication scores and subjective satisfaction in school age group are better than those in preschool group.