Crude shale oil was hydrogenated over a cobalt molybdate-on-alumina catalyst at temperatures of 685, 740, and 800 degrees F; pressures of 600, 1,000, and 1,400 psig; and liquid hourly space velocities of 0.1, 0.15, and 0.3. Hydrogen consumption ranged from 870 to 2,010 scf/bbl and increased exponentially with the degree of denitrification or amount of nitrogen removed. Nitrogen compound types in the crude shale oil and the hydrotreated products were determined by a combination of infrared spectrometry and nonaqueous potentiometer techniques. Nitrogen contents of the hydrotreated products ranged from 1.59 to 0.005 weight-percent. Hydrogen partial pressure had a significantly greater effect on the denitrification rate constants for insole-type nitrogen compounds than on either quinoline-type nitrogen compounds or total nitrogen. The data show that, while at the temperatures and pressures used the denitrification rate constants for quinoline-type nitrogen compounds were greater than the denitrification rate constants for insole-type nitrogen compounds, at pressures above 3,000 psig the opposite would be true.