Allergolam is a new kit (Institute Pasteur Production, Paris) for human basophil degranulation testing (HBDT) and is used to diagnose reaginic allergy.To test the reliability of this kit, we compared the results of HBDT with those of skin tests, RAST and nasal provocation tests in 49 patients. To test its reproducibility, we performed the HBDT four times in one patient, and twice in three patients. To test the specificity of this test to allergens, five patients allergic to Japanese cedar, were tested for house dust allergen (HD).We found a significant correlation between the results of the HD HBDT and HD provocation test and HD RAST. We also found a significant correlation between the results of mite HBDT and mite skin test or mite RAST. There was, however, no significant correlation between the results of HD HBDT and HD skin tests. In regard to the specificity to allergens, HBDT for HD allergen was negative in five patients with Japanese cedar allergy. The test results were not markedly different in two or four repetitions.The above results indicate that HBDT is highly reproducible, specific to allergen and useful in the diagnosis of reaginic allergy. In a comparison of HBDT with RAST, HBDT required a minimum equipment, was easier to perform and almost as reliable as RAST.