To understand the effect of Palm Methyl Ester (PME) mixing on spray combustion characteristics of diesel oil, the intermittent spray flame formed in a high temperature and high pressure combustion vessel was visualized by ICCD camera and analyzed by two color method. The mixing rate of PME to diesel oil was changed up to 60%. It was confirmed that the ignition delay and combustion period were almost equal level. On the other hand, flame temperature and soot production decreased slightly with the PME mixing.