DUTKA, Dominik: Design of the test device for testing the water tightness of axle boxes in accordance with the EN 12 082 standard. [Master’s thesis]. University of Žilina. Faculty of Mechanical Engineering; Department of Design and Mechanical elements. Thesis Supervisor: Ing. Ján Šteininger PhD. Qualification Degree: Engineer (Ing.), Žilina SjF ŽU, 2023.The master‘s thesis deals with the design of a test device for testing the water tightness of axle bearings of railway vehicles. The theoretical part has two chapters, in which one can find information about axle boxes, types of axle boxes, and a description of the water tightness test according to the STN EN 12 082+A1 standard. The practical part proposes the test device using the CAD system. Thanks to it, it will be possible to test different types of axle boxes. The main design elements of the device and their functionality are described. A technical-economic assessment of the device is also prepared.