An experimental study was conducted in a fixed-bed pilot reactor in order to evaluate the effect of catalytic hydrotreating on diesel quality by using feedstocks prepared with different amounts of straight run gas oil, kerosene and jet fuel streams. Experiments were carried out at constant reaction pressure and hydrogen-to-oil ratio of 5.3 MPa and 356.2 mi ml(-1), respectively. The effect of reaction temperature and liquid hourly space velocity were studied in the range of 613-633 K and 1.5-2.0 h(-1) over a commercial Ni-Mo/gamma -Al2O3 catalyst. The experimental information showed that diesel specifications could be reached through single stage hydrotreating of these blends at moderate hydrotreating operating conditions.