Among waterless fracturing fluids, supercritical carbon dioxide (Sc-CO2) has been increasingly emphasized in recent years for hydrocarbon recovery from shale. Sc-CO2 is the most feasible choice to be an alternative to conventional hydraulic fracturing with the ability to alleviate global warming. However, Sc-CO2 fracturing is encumbered with problems such as poor proppant-carrying capacity, easy sand plugging, large displacement, and high frictional resistance. The main aim of this study is to investigate the thickening of Sc-CO2 by adding viscoelastic surfactants (VESs) for increasing the proppant-carrying capacity and to understand the preferential adsorption of this thickened Sc-CO2 over methane on a heterogeneous molecular shale model. From the literature, it was found that a fluorinated polymer provides good CO2 solubility and also thickens CO2. As a result, fluorinated VES, N-ethyl perfluorooctyl sulfonamide (N-ETFOSA), and nonfluorinated VES, N,N,N�-trimethyl-1,3-propanediamine (N,N,N�-TM-1,3-PDA), were used in this study for comparison. The molecular simulation of thickening Sc-CO2 employing N-ETFOSA and N,N,N�-TM-1,3-PDA was carried out at a temperature and pressure ranging from 298 to 305 K and 100 to 7400 kPa, respectively. Although N,N,N�-TM-1,3-PDA shows better solubility in Sc-CO2 than N-ETFOSA, both of them cause an increase in the viscosity of Sc-CO2 by 36 and 156 times, respectively, than its actual viscosity. Adsorption simulations of CO2-thickened Sc-CO2 and methane (CH4) were performed on a heterogeneous molecular shale model. With increasing pressure at a constant temperature, N-ETFOSA-thickened Sc-CO2 showed better adsorption capacity on the molecular shale model than others. Accordingly, at higher pressure, N-ETFOSA-thickened Sc-CO2 shows better selectivity over methane. The results of viscosity and adsorption simulations have been validated by literature experiments. Nonetheless, these outstanding simulation findings need more experimental backup to pave their implementation on real field scenarios. Thus, this study helps establish a theoretical ground for the optimization of shale gas extraction from shale plays and makes it viable storage for CO2 sequestration. © 2021 American Chemical Society.