Carbon monoxide (CO) has long been recognized as a metabolic waste and toxic gas and is also the most common asphyxiating poison that seriously endangers human health. Thus, an adsorption material with high CO adsorption capability is urgently needed. In this study, carbon xerogels (CXs) doped with CuCl were prepared via a sol-gel method and a facile soaking process. The CuCl-doped CXs show the highest CO adsorption capacity of 12.04 cc/g, which is much higher than those of the undoped CXs and activated carbon. Such a high adsorption capacity of the CuCl-doped CXs is not only because of their high porosity but also because of the chemical adsorption induced by CuCl. Moreover, these CuCl-doped CXs exhibit high desorption rate (∼79%), which is beneficial for repeatability.