Moderate hypothermia may reduce mortality in malignant brain infarction. However, due to the extremely limited number of patients treated, it is still unknown whether it may be beneficial if undertaken several days after acute stroke, when the probability of a malignant oedema is higher. We report on a patient with malignant brain oedema after middle cerebral artery infarction, who was treated with moderate hypothermia on the third day after stroke when he became comatose. Hypothermia was induced at a rate of 1.25°C/h by an intravascular cooling catheter. The target temperature of 32°C was reached in about 6 h. After 36 h of hypothermia, the patient was actively re-warmed at a rate of 0.2°C/h. The patient survived and showed a progressive reduction of mass effect on CT scan. This single case study suggests a beneficial effect of hypothermia in the treatment of severe space-occupying ischemic infarction even on the third day after stroke onset.