Objective: To study and optimize the extracting technology of the volatile oil from motherwort fruit. Method: Orthogonal test was used for studying the effect of four extracting factors (extracting pressure

extraction temperature

soaking time

extraction time) and three levels on the fatty oil’s volume by supercritical fluid extraction. Result: The optimum extraction condition of the oil from motherwort fruit was: 50 MPa of extracting pressure

45 degrees

soaking thirty minutes and extracting twenty minutes. Conclusion :The process is scientific and useful for the studying of new drug with fatty oil. The unsaturated fatty acid in the oil was 86.31%.