The main purpose of the Deep Underground Neutrino Experiment is to measure the CP-violation phase in long-baseline neutrino oscillations, proton decay and super nova neutrinos with a liquid-argon detector of unprecedented size. In order to constrain the systematics including the flux, neutrino interaction cross section, energy scale and so on, a near detector is needed to measure the un-oscillated neutrino spectra. The near detector complex will consist of various components since we are aiming to have a good phase space coverage of the neutrino events. A geometry generation tool, DUNENDGGD is developed based on general geometry description (GGD). DUNENDGGD has a great flexibility to generate different
detector and tracker combinations, therefore, the tool has been widely used in the DUNE near detector group, and a large number of studies have been performed based on DUNENDGGD to design the DUNE near detector. In this poster, the concept and examples of DUNENDGGD will be shown.