Malignant external otitis (MEO) is an invasive, morbidity, even mortality, mainly pseudomonal infection of the external auditory canal, frequently involving the base of the skull, multiple cranial nerve and the meninges. In many cases conventional therapy has been prolonged, intensive and relatively ineffective, especially in infections other than bacterial (mainly fungal). We presented theoretical principles of hyperbaric oxygen (HBO) treatment in MEO, our own experience and others' experience in applying this treatment method. We treated eight patients with MEO applying pharmacotherapy, topical management, surgery in one case and also adjunct HBO. In six patients, infection was caused by Pseudomonas aeruginosa, in one by Staphylococcus sp. and in one by Aspergillus sp. Complete recovery was achieved in seven patients. In the patient with MEO caused by Aspergillus sp., intracranial complications developed and the patient died. Our experiences in employing HBO in bacterial-caused MEO have confirmed the role of HBO as a valuable, beneficial, supporting classical treatment method. Small number of patients with MEO, especially with non-bacterial infection, and unforeseen clinical course of disease make our experience difficult to objectivize.