BACKGROUND: The prevalence of allergic disease has increased substantially over the past decades. The reasons for these trends are complex but include increased environmental allergen exposure. Enviro nmental control measures are of particular importance in the prevention and management of allergic disease. Thus, we purposed to evaluate the changes of causative allergens in allergic patients in Chonbuk provincial area that began industralized recently. METHOD: To evaluate the allergens epidemiologically, we performed skin prick tests and RAST in 201 allergic patients from February, 1984 to February, 1985 and 339 patients from February, 1997 to February, 1998. RESULTS: The Following results were obtained. 1) Total sensitization rates did not change significantly (74.2% vs 75.8%, p=0.664). 2) Positive reaction rates to pollens were similar (35.8% vs 30.1%, p=0.17). 3) Positive rates to HDM(house dust mite) were decreased (66.1% vs 56.3%, =0.02). 4) Positive rates to fungi and animal danders were decreased significantly (p<0.001). CONCLUSION: Environmental allergens associated with hygine in Chonbuk provincial areas such as HDM and fungi are decreased significantly during 13 years.