ω3-docosapentaenoic acid (DPA) is an ω3-polyunsaturated fatty acid that has a wide range of human health benefits. Despite its benefits, its natural occurrence is limited in several natural oils such as those obtained from harp seal with its content being no more than 5% in total lipid. Therefore, this study's aim was to find a novel source of ω3-DPA, such as oleaginous microorganisms. It was found that the newly isolated strain Aurantiochytrium sp. T7 showed an ω3-DPA production of 23.5% of the total fatty acids. The cultivation conditions of Aurantiochytrium sp. T7 were characterized, and it was found that the strain grew optimally and showed highest ω3-DPA production with 2% glucose as a carbon source, 1% yeast extract as a nitrogen source and 1.8% salinity at 28˚C and a pH below 5.5. Moreover, ω3-DPA production was observed to increase in the later stage of the cultivation. The characterization of Aurantiochytrium sp. T7 indicated the involvement of a novel metabolic pathway for fatty acids production other than the common fatty acid synthase (FAS) or polyketide synthase (PKS) pathways. Thus, Aurantiochytrium sp. T7 was considered to be promising as a tool for unraveling a novel fatty acid synthetic pathway as well as a producer of ω3-DPA-containing lipids.