This paper reports the results of direct immunofluorescence(DIF)test in 10 patients with pemphigus. In all the biopsied samples

the fluorescence is observed in the intercellular space of the stratum spinosum

diffusely distributed in the whole layer in the form of a honeycomb. The fluorescence of erythematous type and foliaceous type was most prominent in the superficial layer of epidermis. The acantholytic cells exfoliated in the bulla also showed the same fluorescence. By means of immunofluor-escence test

IgG was identified in all cases

a result identical with reports in the literature

In one case of pemphigus foliaceus

in addition to IgG

there also occurred IgM

the significance of which was unknown. C3 deposits were found in 3 cases of pemphigus vulgaris. It was suspected that this change might be the secondary result of tissue injuries. The results indicated that DIP test is very valuble in the diagnosis of bullous dermatoses; especially In those cases which have lesions on the mucous me mbrane only.