Construction and operation of an anaerobic glove box is described mainly built of commercially available material. The box is made of refined steel and has the dimensions of 150 cm in length, 62 cm in height and 68 cm in depth. It is equipped with one round vacuum tight steel airlock for transfer of material. Three Neopren gloves and an oblique glass window are installed into the frontside. The anaerobic box is continuously perfused by 35 l/h of O2-free gas. In the box the atmosphere is whirled round by a fan and hereby led over a layer of catalyst. The O2-content of the anaerobic atmosphere is less than 1 ppm-3 ppm to 4 ppm on a yearly average - measured by an oxygen trace analysor. All bacteriological work as cultivation and isolation of strictly anaerobic bacteria can be done within a continuous O2-free atmosphere by conventional technics. The anaerobic glove box described was used for three years without any failure. In glove boxes built in the same manner as above mentioned similar O2-values will be achievable.