Coenzyme Q10 (CoQ10) is a vitamin-like substance which plays a crucial role in the respiratory chain ranging from bacteria to humans and in the radical scavenging in human body. In this study, the full-length hmgR gene (encoding 3-hydroxy-3-methyl-glutaryl-CoA reductase, HMG-CoA reductase) was cloned and overexpressed in Schizosaccharomyces pombe. Using the pREPG yeast depressed under the thiamine as the control, CoQ10 contents increased up to 2.68 and 3.09 times when recombinant cells were incubated without and with arachidonic acid, respectively. It demonstrated that arachidonic acid could upregulate the activity of HMG-CoA reductase and that hmgR gene played a significant role in CoQ10 biosynthesis. So, it has an importance to be utilized for fermentation.