A two-stage solvent crystallization process was developed for the enrichment of n-3 polyunsturated fatty acids (PUFAs) in free fatty acids (FFAs) derived from saponified menhaden oil. Acetonitrile was used as the solvent in the first stage of the concentration process. At a ratio of acetonitrile to FFAs of 60 mL/g, after 24 h at -40degreesC, the EPA, DHA and total n-3 PUFA contents in the liquid phase could be raised from 15.45%, 9.67% and 32.63% to 28.94%, 18.36% and 60.92%, respectively; with a total n-3 PUFA yield of 90.26%. In the second stage, a mixture of 30% acetonitrile and 70% acetone was used as the solvent. At a solvent to FFAS ratio of 60 mL/g, after 24 h at -80degreesC, the EPA, DHA and total n-3 PUFA contents in the liquid phase could be further raised to 33.85%, 21.35% and 70.77%, respectively, with a total n-3 PUFA yield of 89.03% (overall yield 80.36%).