Hydrocracking of vegetable oils is a prominent technology for the production of biofuels. This work compares the product yields and quality of hydrocracking fresh and used cooking oil under nominal operating conditions, Cracking, heteroatom removal and saturation reaction mechanisms are evaluated for both feedstock types and for three typical hydrocracking temperatures. The assessment of both feedstocks indicates that they are both suitable for high diesel yields with smaller kerosene/jet and gasoline/naphtha yields. As temperature increases, diesel selectivity increases for both feedstock types. However, the used oil feedstock exhibits higher kerosene/jet and naphtha selectivity at low temperatures (350 degrees C) and lower at the highest hydrocracking temperature (390 degrees C).