[en] A description is given of a depleted Uranium (DU)-scintillator hadron calorimeter built as a first prototype for the ZEUS experiment. Tests with this calorimeter are part of a program to optimize several parameters, such as the DU and the scintillator thickness, in order to obtain the best energy resolution for hadrons and jets. Preliminary results obtained with 3.2 mm DU plates and 5 mm scintillator plates are for the hadron resolution 41.5%/√E and for the electron resolution 14.2%/√E, for beam momenta up to 9 GeV. Replacing the Uranium by 4 mm thick lead plates, leads to a hadron resolution ∼60%/√E, and an electron resolution of 13%/√E. (Auth.)