Disclosed are a bacterium producing DHA and/or EPA, 6 gene fragments of the genome of the bacterium and the use thereof. The bacterium is Schizochytrium limacinum HS01 with the deposit number in China General Microbiological Culture Collection Center being CGMCC No.13746. The 6 gene fragments consist of gene fragment 1 to gene fragment 6, and the nucleotide sequences are sequentially as shown in sequence 3 to sequence 8 of the sequencing listing. Experiments prove that, a fermentation broth containing DHA and EPA is obtained through fermentation cultivation of Schizochytrium limacinum HS01; the gene fragments 1-6 are introduced into the Schizochytrium limacinum MYA-1381 to obtain a recombinant bacterium; and the capability of the recombinant bacterium to produce DHA and EPA is greatly improved. The bacterium, 6 gene fragments, proteins encoded by the 6 gene fragments, and a vector, cell or organism containing the 6 gene fragments provided by the present invention all have an important application value.
