Production of synthetic diesel fuel by the Fischer-Tropsch (FT) method in the presence of a composite catalyst prepared by mechanically mixing 35 wt % Co/SiO2, 30 wt % HZSM-5, and 30 wt % Al2O3 has been studied. The catalyst has been characterized by the H-2 TPR, H-2 TPD, NH3 TPD, XRD, SEM, and TEM methods. Catalytic properties have been studied in a fixed-bed flow reactor at 2 MPa and a GHSV of 1000 h(-1) in the temperature range of 230-250A degrees C. The highest efficiency and C5+ HC selectivity values of 130 kg/(m(3) h) and 72.5%, respectively, are achieved at 250A degrees C. The low-temperature properties of the synthetic diesel fuel meet the requirements for winter diesel.