Abstract: This study reports the synthesis of mixed oxides of Mo, and Ni nanostructures on ᵞ- Alumina as support, by utilizing ammonium hepta molybdate(AHM), nickel nitrate, as precursors, and organic additives such as citric acid, ethylene diamine tetra acetic acid (EDTA), and urea were used as chelating agent and different pH, in order to investigate the effects of additive structure and pH variation on chemical and physical properties, morphology, size of nanocatalyst and interaction of active metals with support. Also, this study evaluated the activity of catalysts and compare with commercial catalyst. The metal oxide nanoparticles were prepared and impregnated using wetness impregnation method on ᵞ- Alumina in-situ. The supported nanocatalyst was calcined to remove the volatile material and gases. The nanocatalyst prepared using organic additive,EDTA as surfactant showed enhanced catalytic activity for the oil residue hydrodesulphurization which contained 21000 ppm sulfur. The sulfur content of the feed was reduced to 3000 ppm at 380°C and LHSV 1.5h-1 showing a good catalytic activity