AbstractHouse dust mite (HDM) is the most common allergen exacerbating atopic dermatitis (AD), and allergen‐specific immunotherapy (AIT) using HDM exhibited significant improvements in previous studies. Alopecia can occur as a complication of AD. Alopecia totalis (AT), a severe form of alopecia areata (AA), does not respond well to treatment and the chance of full recovery is less than 10%. For extensive hair loss, topical immunotherapy such as diphenylcyclopropenone (DPCP) is used as the first‐line treatment. However, since DPCP is a kind of contact allergen, it has the potential to exacerbate AD. A 38‐year‐old man with AD and AA visited our clinic with symptoms worsening from 3 months ago. Although taking oral methylprednisolone (8 mg/day) and cyclosporine (100 mg/day) for 3 months, he has lost over 90% of his hair and the Eczema Area and Severity Index (EASI) was 43. Total serum immunoglobulin E (IgE) levels were 4454 kU/L (normal <100 kU/L) and the specific IgE levels for Dermatophagoides pteronyssinus and Dermatophagoides farinae following ImmunoCAP® were 20.8 and 37.4 kU/L, respectively. This patient did not respond well to previous treatment and was reluctant to use long‐term steroids, so subcutaneous AIT using HDM was administered along with oral cyclosporine (100 mg/day). Topical tacrolimus was also applied to the AD lesions throughout the body. To reduce itching, nonsedative antihistamines were used if necessary. Hair loss was almost completely improved 1 year after the AIT initiation and the skin lesions of AD also improved (EASI 2.4). The specific IgE levels for D. pteronyssinus and D. farinae were 3.73 and 7.16 kU/L, respectively. Herein, we report a patient with promising results following AIT for AT with severe AD. In severe alopecic patients with AD refractory to conventional treatment, including immunosuppressants, AIT could be considered as a treatment option.