Lipase-catalyzed synthesis of DAG was produced with soybean oil in a solvent-free system by Lipozyme RM IM.Effect of substance ratio（soybean / glycerol）,the amount of enzyme,reaction temperature and reaction time on diacylglycerol yield was investigated.The results of orthogonal experiment showed the optimal conditions were as follows: substance ratio 2: 1,the amount of enzyme 11%,the reaction temperature of 60℃,the reaction time 12 h,DAG yield of 52.6%.It provides a new way for the synthesis of diacylglycerol and provides a theoretical reference for synthesis diacylglycerol in lipase-catalyzed solvent-free systems.