Abstract: The device in accordance with the invention for the sterilization of a hose coupling device (in its connected condition) of dialysis apparatus, comprises an opening housing into which the coupling device is placed. The coupling device is subjected to infrared radiation from heating elements in the housing whose heating effect is monitored and automatically controlled by a temperature probe arranged under the coupling device in the housing. Since the temperature probe is designed to have such an infrared absorption characteristic that the temperature increase rate of the probe is substantially the same as that of the coupling device, one may be certain that the coupling device will have reached the desired temperature (which is detected at the temperature probe) with only a slight delay if any. At the same time there is the advantage that the interior of the coupling device is heated to substantially above the minimum necessary sterilization temperature.