Abstract: Chromatographic analysis of petroleum products for the determination of qualitative and quantitative composition is comparable in complexity with the analysis of biological materials. The production of gasoline and intermediate liquid petroleum products with a similar composition is extremely important from an economic point of view. Detailed hydrocarbon analysis is widely used in Russia in order to improve the quality control of the products. This article considers an algorithm of qualitative gas chromatography–mass spectrometry analysis, which makes it possible to decrease errors in the identification of components in the test samples of petroleum products.