PURPOSE: To simultaneously carry out the hydrodenitrogenation and hydrocracking in a collective hydrodesulfurization step for a crude oil or the crude oil from which a naphtha fraction is removed and increase the production of high-quality kerosene and light oil and simplify refining equipment by using a specific catalyst.

CONSTITUTION: This method for hydrotreating a crude oil is to carry out the hydrotreating of a crude oil or the crude oil from which a naphtha fraction is removed in the presence of a catalyst supporting a metal selected from groups VI, VIII, IX and X of the periodic table (preferably a combination of Ni-Mo, Co-Mo, etc.), on an alumina-phosphorus carrier under conditions of preferably 360-420°C reactional temperature, 100-180kg/cm2 partial pressure of hydrogen, 500-1000Nm2/kl hydrogen/oil ratio and 0.15-0.5hr-1 liquid hourly space velocity(LHSV). Furthermore, the catalyst is preferably prepared by supporting the metal in an amount of 5-30wt.% expressed in terms of metallic oxides based on the total weight of the catalyst on the alumina-phosphorus carrier containing 1-18wt.% phosphorus oxides and the average pore diameter thereof is preferably 90-200.