A new testing device for cyclic loading of specimens with a novel shape design is presented. The device was applied for investigations of fatigue of metallic specimens under pressurized hydrogen up to 300 bar at tem-peratures up to 200 C. Main advantage of the specimen design is the very small amount of medium, here hydrogen, used for testing. This allows experiments with hazardous substances at lower safety level. Addi-tionally no gasket for the load transmission is required. Woehler curves which show the influence of hydro-gen on the fatigue behavior of austenitic steel specimens at relevant service conditions in hydrogen powered engines are presented. Material and test conditions are in agreement with the cooperating industry.