Background and Purpose: The effects of hyperbaric oxygen (HBO) therapy on humans are uncertain. We aim to study the possible beneficial effects and side effects of HBO treatment.Methods: 30 stroke patients randomized, 15 to hyperbaric treatment with 100% oxygen at a pressure of 1.5-2 ATA in Monoplace or Multiplace chamber for 90 minutes daily for 60 days and 15 to physiotherapy daily for 60 days. The effects of treatment will be evaluated by a questionnaire. Evaluation both given at the beginning of the program and again at the end in both groups.Conclusions: We did not observe the major side effects usually related to HBO. Accordingly, it can be assumed that hyperbaric oxygen might be safe. We hypothesize that HBO might improve outcome after stroke, as we detected an outcome trend favoring HBO therapy. A large randomized trial might be required to address the efficacy of this therapy.