Background/Aims: The use of unproven complementary/alternative medicine (CAM) to treat allergies is popular in Korea. We conducted a multicenter survey of the current use of CAM other than herbal medication in Korean allergy patients. Methods: This study enrolled 510 adults with allergic diseases, including asthma, allergic rhinitis, atopic dermatitis, and chronic urticaria, from ten hospitals. They underwent a structured questionnaire interview and clinical assessment of the prevalence, motivation, costs, and subjective assessment of CAM. Results: Of the patients, 16.7% used at least one type of CAM to treat their allergic diseases. Common types of CAM were diet (48.6%), aroma therapy (23.8%), massage (14.3%), breathing exercises (7.6%), baths (5.7%), and mind control (5.7%). The therapeutic effects of CAM included "improved" in patients using mind control (50%), diet (50%), breathing exercises (75%), and baths (33.3%), but "worse" in patients using aroma therapy (28%), and massage (26.7%). About 36.4% of the patients used CAM more than four times per year, and the average cost per CAM user was 370,000 won/year. The main reason for trying CAM was `hope to improve my constitution`. Conclusions: CAM is used widely for treating allergic diseases in Korea. Detailed knowledge of CAM and patient education are important. Further studies of the clinical efficacy of CAM are needed