Clinico-morphological characteristics of 105 acrospiromas surgically removed within 10 last years is presented. In 6 patients the tumour was considered as a malignant acrospiroma which, according to the literature and the authors' material, is prone to recurrence. The features of a diagnostic significance are discussed in detail: the development of tumour in the cyst, growth of squamous cells and clear (due to the glycogen) cells, formation of structures resembling the sweat glands ducts. Electron-microscopic examination indicates the histogenetic link of acrospiroma with the elements of sweat gland ducts (intracytoplasmic ducts, periluminal cells, the lack of clear signs of secretion). All this relates also to the tumour described in the literature as a clear-cell hydradenoma.