Life on Mars has been a great source of motivation for human beings in recent years. Although this motivation has different reasons, human beings will achieve a sustainable life on Mars. The idea of establishing a colony on Mars will be possible by offering a suitable and sustainable life to the pioneers. In this study, a structure as a living module was designed and CO2, which is produced by metabolic activities, distribution all over the module is examined. For the CO2 distribution analysis, ANSYS Fluent software is used and it is assumed that the pressure for the indoor environment would be 60% of the Earth's sea-level pressure. In these environmental conditions, where gravity is thought to be minimal, it is intended to prevent the accumulation of carbon dioxide near the faces of the crewmembers and to distribute oxygen uniformly with a reasonable velocity and flow rate into the breathing zone.