The oil plants provide a sufficient source of renewable lipid production for alternative fuel and chemical supplies as an alternative to the depleting fossil source, but the environmental effect from these plants' cropping is a concern. The high oleic acid (OA; C18:1) content in plant -derived products provide advantages of multiple uses with improved oxidative stability and a wide range of applicable temperature. Here we used a promising lipid producer, the oleaginous yeast Rhodosporidium toruloides, to attempt to obtain an OA -enriched lipid. Saccharomyces cerevisiae OLE1 (ScOLEI) gene encodes Delta 9 fatty acid desaturase (Delta 9FAD), which is generally known to synthesize palmitoleic acid (POA; C16:1) and OA, but the functions of putative It toruloides d9FAD gene are not well understood. In a complementary test, the Rt Delta 9FAD gene rescued the survival of an OA -deficient Scolel Delta mutant, and we introduced the Rtd Delta FAD gene into IL toruloides strains for the production of OA -enriched lipid. Increasing lipid production was observed in ScOLEI and genomic Rtd Delta FAD gene-overexpressing R. toruloides strains. The ScOLE1 transformant output fivefold more OA content in total amount, with >70% of total lipid. Different enhancing effects from the protein coding sequence and genomic sequence of Rtd Delta FAD genes were also observed. Overall, this study resulted in ScOLEI and Rtd Delta FAD gene overexpression in R. toruloides to obtain OA -enriched lipid as a candidate source of designed biodiesel and lipid -related chemicals. (C) 2018, The Society for Biotechnology, Japan. All rights reserved.