The Nubian houses represent a good example of balanced interaction with the surrounding environment. Where the environment plays a major role in shaping the Nubian houses and their architectural vocabulary, which has emerged through the success of these houses in controlling and creating a comfortable living environment for the interior spaces. The comfort conditions are not available in the new housing located in the Karkar Valley, which was established by the state to settle the Nubians around Lake Nasser, where the buildings came in a typical repetitive form without considering the natural characteristics of the surrounding desert environment as in the traditional Nubian houses. So, the main aim of the research is to improve the thermal performance of the modern Nubian houses. The study relied on numerical simulation, using (Autodesk Simulation CFD 2016) as one of the programs based on the calculation of fluid dynamics to measure the temperature, relative humidity and air velocity of the spaces of the house. The results of the calibration of the program show that this simulation method can predict the thermal performance of these houses and the impact of their various components. The simulation results for the improved model indicate a temperature drop of (2.8 K) and increase the natural ventilation rate to (0.9 m / s) within internal spaces, which in turn helps to feel the thermal comfort.