The adsorption of asphaltene onto different carbonaceous nanostructures including reduced graphene oxide (rGO), multiwall carbon nanotubes (MWCNTs), carbon black (CB), and activated carbon (AC) was studied. Graphene oxide was synthesized via Hummers' method and reduced in a thermal shock to prepare rGO. Asphaltene was extracted from a heavy oil sample and characterized. The textural and structural properties of the carbonaceous nanostructures were characterized by Brunauer-Emmet-Teller surface area measurement, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and temperature-programmed desorption. Asphaltene was dissolved in a solution of 37 vol % heptane in toluene (Heptol) to prepare heavy oil model solutions. The carbonaceous nanostructures were added to the model oils, and the kinetics as well as the equilibrium adsorption and desorption of the asphaltene onto the adsorbents were studied. The pseudo-second-order kinetic model best explains the asphaltene adsorption onto the carbonaceous adsorbents. The time required to approach equilibrium adsorption of the asphaltene is 1, 4, 12, and 24 h over rGO, MWCNTs, CB, and AC, respectively. The adsorption isotherm of the asphaltene onto rGO follows Langmuir model, while Freundlich isotherm bets fits the asphaltene equilibrium adsorption onto MWCNTs and CB. Among the carbonaceous adsorbents, the rGO sample exhibits the highest asphaltene adsorption capacity of 640 mg/g, about 5.7, 2.4, and 1.2 times as high as that of AC, CB, and MWCNTs, respectively. The adsorption of the asphaltene onto AC is found to be diffusion-limited. This is ascribed to the micropores present in the AC structure. Water content of the model oils has no effects on the asphaltene adsorption capacity of the carbonaceous adsorbents. The heat of adsorption of the asphaltene is calculated to be in the range of -11.51 to -22.49 kJ/mol, indicating strong and nearly irreversible polar, pi-pi and pi-polar interactions of the asphaltene with the surface sites of the carbonaceous nanostructures.