Effects of solvents, extraction temperature, ratio of the raw material to weight the solvent volume, size distribution of raw material and extraction the time on ultrasonically aided solvent extraction of coix lacryma-jobi seed oil were studied. The results of orthogonal experiment indicate that the effectiveness of these factors on oil yield is in this order: sizes of raw material> extraction temperature extraction time power and frequency of ultrasound> ratio raw material weight to the volume of solvent. A series of parameters optimized by orthogonal experiment are as follows: extraction temperature is 50°C, size of raw material is 60-80 mesh, ratio of feed stock weight to solvent volume is 1:3.5, extraction time is 40 min, ultrasonic power and frequency is 25 kHz and 300 W respectively. ; Department of Applied Biology and Chemical Technology