A 52-year-old woman developed headache with fever followed after several days by a left hemiplegia, paralysis of the right IIIrd, Vth, and VIIth cranial nerves, and a right cerebellar syndrome. The CSF contained 48 white cells/mm3 and 0,80 g/l of proteins. Blood and CSF cultures were negative. In spite of an early massive antibiotic therapy, successive CT scans demonstrated the development of a voluminous rhombencephalic abscess. Clinical improvement occurred only after 1 month of treatment. The diagnosis of listeriosis, suggested clinically, was confirmed by elevated levels of antibodies to listeria Monocytogenes serotype 01 (1/80 to 1/1 280). Signs regressed slowly and hemiplegic sequelae persisted. A review of the literature demonstrated the rare nature of listerian abscesses in the CNS: in 6 of the 9 cases reported the patients were immunodepressed and the abscess was located in the cerebral hemispheres. The elective rhombencephalic lesion of listerian encephalitis may also apply to abscesses, which can develop in previously healthy subjects. The clinical picture is that of a solitary brain stem abscess with a fatal outcome whatever the nature of the germ. Van Gilder, Allen and Lesser (1974) published the first report of a case that recovered after surgical drainage. The present case is the only one of the 6 cases reported in the literature in which a favorable outcome was obtained by antibiotic therapy.