The possibility of qualitative analysis of heavy hydrocarbon mixtures by differential scanning calorimetry (DSC) and quantitative analysis combined with thermogravimetry (TG) was demonstrated. In experimental conditions that ensure complete oxidation of the sample on heating, successive oxidation and evaporation of paraffins, light and heavy aromatics, and naphthenes, resins, asphaltenes, and carbenes take place. Crudes of different classes (waxy, naphthene -paraffin, naphthene bases) and geological age were investigated. Methods of qualitative and quantitative analysis by TG-DSC are reported.