The effects of molecular weight of polyethylene glycol (PEG), various salts and broth loading on the partitioning of lipase from cell free fermentation broth of Rhodotorula glutinis were studied in PEG/salts aqueous two-phase systems at pH 6.6 and 24 degrees C. With the application of 17.5 (%, w/w) PEG4000/12.5 (%, w/w) oxalate potassium and 12.5 (%, v/w) fermentation broth loading was found most appropriate since high lipase purification factor of 13.9, and yield of enzyme in top phase 71.2% were obtained. The value of K-e decreases as the PEG molecular weight increases. (C) 2013 Elsevier B.V. All rights reserved.