Introduction: Allergic rhinitis (AR) is a disorder with high prevalence worldwide. Identification of clinically relevant allergens is the key step for the diagnosis, allergen avoidance and allergen specific immunotherapy for AR. Areas covered: With the new findings of mechanisms of AR and the development of technology, much progress has been achieved in the diagnosis of AR recently. We review the recent advances about local IgE, in vivo and in vitro tests, cytological diagnosis and nitric oxide (NO) in the diagnosis of AR. Expert commentary: AR is traditionally diagnosed with the combined evaluation of history and allergen sensitization by in vivo skin prick tests and in vitro allergen specific IgE in serum, to confirm the correlation between clinical history and potential allergens. Nasal provocation test and local IgE measurement can be used to diagnose local AR. Allergen microarray has the ability to detect more potential allergens. Basophil activation and mast cell activation tests can be used in allergen diagnosis and to modify the response to immunotherapy, while cytological diagnosis is useful in the differential diagnosis of AR and non-AR. Nasal NO has been confirmed to be an optimal biomarker to discriminate between AR and non-AR.