The solvent crystallization separation process of oleic acid and linoleic acid was investigated by using methanol solvent. The results show that the crystallization temperature and the proportion solvent have big influence on the solvent crystallization separation process of oleic acid and linoleic acid. Decreasing crystallization temperature decreases the mass fraction of oleic acid in crystal and increases the mass fraction of linoleic acid in filtrate. Decreasing proportion solvent increases the mass fraction of oleic acid and linoleic acid. The magnetic field has influence on the separation process, it is favorable to the solvent crystallization separation process of oleic acid and linoleic acid. The quantitative results show that under the effect of magnetic field the mass fraction of oleic acid in crystal increases by 1.73％～2.48％ and the mass fraction of linoleic acid in filtrate increases by 1.68％～3.19％.