Abstract: Fructus broussonetiae oil contains rich linoleic acid for human body,which has high potential pharmaceutical value.In order to remove saturated fatty acids and purify linoleic acid in F.broussonetiae oil,a method was developed for purification of linoleic acid,which included saponification,hydrolysis and freezing.Raw F.broussonetiae oil was saponified,in the alkali base of 35% self-weight at 80-90℃.The freezing procedure was carried out at-8 to-10℃ after adding 5 time weight of acetone for 48 hours.The purified content of linoleic acid was raised from 65% to 88%.