Patients diagnosed with bronchial asthma (BA) were prospectively enrolled to assess their allergen spectra and atopic status. The patients came from five major cities (Ankara. Ízmir, Samsun. ElazíǵC, and Adana) in different regions of Turkey. Atopic status, total IgE levels, and allergen speelra were determined in 1149 patients and 210 controls who were spouses of the patients sharing the same environment hut not consanguinity with the patients. Total IgF. levels were significant higher in the asthmatic patients. For both groups, total IgE. levels were higher in both alopic and male subjects. Atopy rates were 42% in asthmatics and 26.1% in controls, declining notably by age in both groups. The most common allergen in both groups was house-dust mite (RDM), which was more frequency detected in coastal regions (Samsun. Izmir, and Adana). Allergen spectra of the patients included HDM. pollens, cockroach, pet animals, and molds in decreasing order of frequency. Phleum praiensi: and Artemisia vulgam were the most common pollens in all regions, whereas Olea europaea was the most common in Izmir. Pollen sensitivity was least frequent in hlazig. For all of the regions, pet sensitivity was less common than, and mold sensitivity was comparable to, that of Western countries. In conclusion. BA patients in Turkey displayed significant differences in their allergen spectra and total IgE levels from control subjects and BA patients in Western countries.