Dehydroepiandrosterone is a long established neuroactive steroid. Some authors documented that 7-oxygenated derivatives of this steroid may be responsive at least by part for its physiological activity. In the ventricular cerebrospinal fluid obtained from 15 patients with hydrocephalus (8 postmenopausal women and 7 men) potentially neuroactive steroid 7-oxygenated derivatives of dehydroepiandrosterone were quantified using gas chromatography/mass spectrometry. Besides free dehydroepiandrosterone 7-oxygenated steroids such as 7 alpha- and 7 beta-hydroxy-dehydroepiandrosterone, 5-androstene-3 beta,7 alpha,17 beta-triol and 5-androstene-3 beta,7 beta,17 beta-triol in picomolar concentration in serum and cerebrospinal fluid were found. Dehydroepiandrosterone and its 7-oxygenated derivatives are present in ventricular cerebrospinal fluid in concentration 2-100 times lower than in serum.