The proteins from 15 types of cultivar of hot peppers cultivated in Korea were extracted and its allergenicity was investigated by immunoblotting and enzyme-linked immunosorbent assay (ELISA). The immunoblotting of hot pepper proteins extracts (HPEs) against serum of hot pepper sensitized patients revealed dominant IgE binding to 14, 37, and 40 kDa molecules. The specific levels of IgE to HPEs sample No. 1, 3, and 7 were much higher than the other samples in patients. Also, IgE binding capacity of HPEs were not reduced by thermal processing and digestion in ELISA using human IgE antibody acquired from hot pepper sensitized patients. By means of Western blotting using anti-thaumatin IgY, thaumatin-like protein (TLP) acting as allergen in several plants and fruits was detected in tested hot peppers. This study demonstrates that the antigenic protein in hot peppers are present but are differently contained according to cultivars.