The yeast Yarrowia lipolytica Pot g is one of the oleaginous microorganisms with a potential for biodiesel production. Sub-critical water (SCW) treatment has been known as an effective method for increasing the amount of extractable lipids in microorganisms. In this work, the amount of neutral lipids and fatty acid profiles in neutral lipids extracted from Y. lipolytica Po1g with and without SCW pre-treatment were investigated. The effects of temperature (125, 150 or 175 degrees C), amount of water (20, 30 or 40 mL/g biomass) and time (10,20 or 30 min) showed that maximum neutral lipid (42.69%, w/w) could be achieved at 175 degrees C using 20 mL water for 20 min. The maximum neutral lipid from unpretreated samples was 23.21%. No difference in fatty acid profiles was observed, but long chain fatty acids were observed in higher amount in SCW pretreated samples. SCW pretreatment increased biodiesel yield twofold. (C) 2012 Elsevier Ltd. All rights reserved.