Abstract: The present disclosure relates to genetic engineering and biosynthetic technologies, and provides a biosynthetic method for preparing 10-HDA and use thereof in skin care. An engineered yeast strain is fermented in a culture medium containing trans-2-decenoic acid to produce 10-HDA. In vitro evaluations using a 3D epidermal model and skin fibroblasts indicate that 10-HDA can increase stratum corneum lipid parameters including ceramides and fatty acids, reduce UV-A-induced DNA damage markers, improve mitochondrial function by decreasing mitochondrial ROS and early apoptosis and increasing ATP and NADPH, and increase relative telomere length under oxidative stress, thereby providing potential benefits for skin barrier repair and anti-aging skin care products.