A permanent filter for a medical sterilization container is provided. The permanent filter is made from a ceramic. The ceramic is made from globular substrate grains. A medical sterilization container is also provided, in particular for receiving and storing objects to be sterilized, having a container bottom part and a container top part for closing the container bottom part in a closed position of the sterilization container. At least one of the container bottom part and the container top part have a gas exchange orifice, which is closed with a permanent filter. The permanent filter is made from a ceramic and the ceramic is made from globular substrate grains. In addition, a method is provided for producing a permanent filter for a medical sterilization container. The permanent filter is produced from a ceramic material by sintering. Globular substrate grains are used as the ceramic material.