A comparative study of dispersed catalysts obtained in-situ on the based of Mo and Fe-Co in the process of catalytic steam cracking of vacuum residue in the slurry-reactor was conducted (water : vacuum residue = 0,1 : 1 ratio, temperature – 450 °C, pressure – 2,0 MPa, feed rate – 0.1 kg/h). Samples of the semisynthetic oil were obtained and characterized. In the rectification process the gasoline, diesel, oil and residual fractions were allocated. A complex of physicоchemical methods was applied to the analysis of light and dark petroleum products. Based on the obtained data the performance properties of the studied fractions were compared. The relationship between the redistribution of components within the fractions and the catalytic properties of dispersed catalysts was established. The efficiency of using Fe-Co catalysts to produce semisynthetic oil with an increased content of light fractions in the process of catalytic steam cracking of vacuum residue is shown