Transmission electron microscopy (TEM) was used to study the structure of particles of CO2-asphaltenes precipitated from a goudron vacuum residue sample in the gas anti-solvent (GAS) process using heptane, toluene, and their mixture (heptol) as diluents. It was shown that CO2-asphaltenes, despite lower aromaticity and polarity compared to C-7-asphaltenes, have a similar irregular layered internal structure, as well as a close distribution of the aromatic layers and similar distance between the layers in the packed crystallites.. The type of the diluent used affects not only the yield and composition of the precipitated CO2-asphaltenes, but also the degree of order and the size of layers of aromatic fragments of the molecules forming their structure. In this respect, toluene as a diluent ensures the formation of CO(2)asphaltenes that are comparable to C-7-asphaltene particles in their molecular structure and structural parameters.