Native or modified lecithins are widely used as a multifunctional ingredient in the food industry. A fractionation process of sunflower lecithin (a non GMO product) with absolute ethanol was used for obtaining enriched fractions in certain phospholipids under different experimental conditions (temperature 35-65 °C, time of fractionation 30-90 min, ethanol/lecithin ratio 2:1, 3:1). Phospholipid enrichment in PC and PI fractions was obtained and analyzed by 31P NMR determinations. The percent extraction coefficients for different phospholipids (%EPC, %EPE and %EPI) in both fractions were calculated. Values of %EPC in PC fractions significantly increased (p < 0.05) from 12.8 (35 °C, 30 min, 2:1) to 57.7 (65 °C, 90 min, 3:1) at increasing temperature and incubation time. %EPE varied from 3.0 to 18.3 in the same fraction while %EPI presented lower values (<3%) under all the conditions assayed. The study of the effect of the operating conditions on the fractionation process evidenced a relevant influence of temperature, incubation time and to a minor extent of the ethanol/lecithin ratio on the enriched fraction yield% and selectivity of the main phospholipids (PC, PI, PE) estimated by %EPL. Response surface methodology (RSM) was utilized to explain the influence of the different parameters to optimize this process. © 2008 AOCS.