The newest European high performance material testing reactor, the Jules Horowitz Reactor, will support existing and future nuclear reactor designs. The reactor is under construction at CEA Cadarache research center in France and is expected to start operation at the end of this decade. This paper presents the Computational Fluid Dynamics simulation of the reactors hot fuel element. Moreover conjugate heat transfer analysis is performed for the hot channel. The main objective of this work is to improve the thermal-hydraulic knowledge of the complex hot fuel element and to present the most prominent finds. Possible improvements for the future work are suggested.