The invention relates to a method for completely separating oleic acid and linoleic acid, which comprises the following steps: fully shaking the solvent system, standing for phase splitting, and separately collecting an upper phase and a lower phase; dissolving 70-80% of high-purity oleic acid in the upper phase, and separating by adopting high-speed countercurrent chromatography, wherein from sample injection, the positive rotation is firstly carried out, the upper phase is taken as a stationary phase, and the lower phase is taken as a mobile phase, so that a mixed solution of linoleic acid and the lower phase is obtained; then, the lower phase is taken as a stationary phase, the upper phase is taken as a mobile phase, mixed liquid of oleic acid and the upper phase is obtained, and the lower phase and the upper phase are removed to respectively obtain linoleic acid and oleic acid. According to the invention, oleic acid with the purity of more than 99% is obtained by separating and purifying 70-80% high-purity oleic acid by using a high-speed counter-current chromatography technology for the first time, all reagents of a solvent system can be recycled, and the oil acid can be theoretically recovered by 100%.
