The heat treatment of deep drawing distillation process of used engine oil was studied in this paper, as a result,the viscosity (40 ℃) of two waste oils decreased by 36.20% and 48.79% respectively, the total reduction extent of the heteroatoms was 56.11% and 50.25% respectively, the total reduction extent of the mixed elements was 86.81% and 87.12% respectively, therefore, the process achieved the purpose of viscosity reduced and impurity removed. The recovery rate of used engine oil after deep drawing by distillation was up to 89.72%, besides, the raw oil can be used to Hydrogenation refining, which had lower viscosity, less heteroatoms and mixed elements.