The main motivation of the development of hydrodearomatization of middle distillate is the growing demand for high quality (low sulphur-, nitrogen- and aromatic content) gas oils for transportation and for economical production of light olefins (ethylene, propylene). The results of hydrodearomatization of different sulphur and nitrogen containing real gas oils from Hungarian and Russian crudes on Pt,Pd/USY zeolite, amorphous Pt,Pd/SiO2-Al2O3 and Pt,Pd/Al2O3 catalysts with different ratio of Pd/Pt are presented. Additionally, the effect of sulphur and nitrogen contents of feeds and process conditions on HDA, HDN and HDS activities was studied. The Pt-Pd/USY catalyst having Pd/Pt atomic ratio of 4:1 was the most active in hydrodearomatization of high sulphur and nitrogen containing feeds. At favourable process conditions excellent quality (sulphur: 1-6mg/kg, nitrogen: 1-3 mg/kg and aromatic content: 5-15%, cetane number: 53-56) diesel fuel blending component can be produced with high gas oil yield, which is an excellent feed for steam cracking either.