Pemphigus herpetiformis is a rare clinical entity belonging to the group of autoimmune blistering disorders of the skin, that usually presents clinical features of dermatitis herpetiformis and immunologically findings of pemphigus. Because of the variety of its presentation, differential diagnosis with other bollous diseases is not simple and histopathological results have to be supported by direct immunofluorescence assay, for a correct diagnosis. We report the case of a young woman, where immunofluorescence was a fundamental tool to reach the diagnosis of pemphigus herpetiformis, because of the lack of acantholitic cells at histological sample.