An ultra-sound testing device for gas pressure accumulators is used to test a predeterminable set position that can be taken by a movable separating element (20) inside an accumulator (10) that can be filled with gas and connected to a fluid circuit. The separating element (20) has at least one testing body associated with a visible mark (34) which indicates the set position of the separating element (20), and on the basis of which an ultra-sound testing device provided for the respective testing body can be set on the accumulator (10). This testing device allows a plurality of accumulators of the same type to be tested for their predeterminable gas pressure set value, which corresponds to the gas pre-filling pressure, by means of a single hand apparatus. This kind of test is economical and achieves reliable results.
