Experimental studies have been conducted on the co-hydroprocessing of canola oil-heavy vacuum gas oil (HVGO) blends with different blending ratios under typical hydroprocessing conditions. It was found that the HVGO-canola oil blend feeds had higher conversion to light product than the pure HVGO feed at similar operating conditions. However, the hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) were not affected by the addition of canola oil into the HVGO. Under similar conversion or light product yield, coprocessing HVGO-canola oil blends required lower temperature and/or pressure than hydroprocessing the pure HVGO, an implication of potential energy saving. It was also found that at the same conversion, the HVGO-canola oil blends generated more diesel but less gasoline than pure HVGO, an effective way to meet the fast increasing diesel demand.