Chromium is one of the representative toxic substance by occupational exposure which damage the mucosa of respiratory tract including nasal septal perforation. The aim of this study is to evaluate the effect of chromium exposure on olfactory function and to obtain the fundamental information about chromium exposure. The authors performed olfactory function test, laboratory tests and questionnaire interview on the subject of three groups, that is, two exposed groups and one nonexposed group from May 1 to June 30, 1994. Exposed group 1 was 15 male workers without nasal septal perforation, exposed group 2 was 15 male workers with nasal septal perforation among 103 workers in 22 chromium plating factories, and nonexposed group was 15 male medical students. The gathered informations were histories of chromium exposure, habits of smoking and alcohol drinking, the concentrations of chromium in serum and urine, and asparate aminotransferase(AST), alanine aminotransferase(ALT), gamma-gluutamyl transferase,etc. Olfactory function was checked by T and T olfectometer using phenyl ethyl alcohol(material A), methyl cyclopentenolone(material B), iso-valeric acid(material C), gamma-undecalactone(material D), skatole(material E) and the results were expressed by detection threshold(DT) and recognition threshold(RT). There was a significant difference between exposed groups and nonexposed group in A, B, C, D, E substances by DT and in A, B, C, D substances by RT(p<0.01) The degree of olfactory dysfunction was highest in the exposed group 2 and lowest in the nonexposed group in all five substance by Dt and it was same in A B, D substance RT and the difference of RT and DT. As summary, olfactory dysfunction by chromium exposure was recognized and the degree of olfactory dysfunction was higher in the exposed group with nasal septal perforation. Therefore, it would be helpful to apply olfactory function test for the early detection of olfactory dysfunction, and this test would be considered as the basic tool within workers' compensation system.