Abstract: The phosphatidylcholine was purified from soybean lecithin powder by mixed solvent. The influence factors ( mixing solvent ratio of 1-ethyl-3-methylimidazolium hexafluorophosphate ( EmimPF6) and methanol, solid-liquid ratio, extracting temperature and extracting time) of separation were investigated by single factor experiment. The purified phosphatidylcholine products ( with purity 87.65% and extracting yield 70.76%) were obtained based on response surface experiment at the conditions as follows: extracting time 60.12 min, mixing solvent ratio ofEmimPF6and methanol 2.95 ∶ 1 ( v/v) , solid-liquid ratio 1 ∶ 7.50 ( g/m L) , and extracting temperature 30.53 ℃. The phosphatidylcholine was purified by aluminum column chromatography and the purity of final product was 98.85%.