The fatty acid dehydrogenase I (FatI) is able to express in mammalian cells and convert n-6 polyunsaturated fatty acids (PUFAs) to n-3 PUFAs. n-3 PUFA is an important component of the cell membrane and plays an important role in the prevention and control of a variety of human diseases. However, n-3 PUFAs cannot be endogenously synthesized by mammals because they lack the dehydrogenase that converts n-6 to n-3 PUFA. For the time being, gradually matured transgenic technology makes it possible to produce transgenic animals that are able to synthesize n-3 PUFAs by themselves. However, the transgenic technology itself may bring negative impacts. In this study, the eukaryotic expression vector pcDNA3.1-FatI was introduced into the genome of Boer goat fetal fibroblasts cultured in vitro, and the influence of biological characteristics of the fetal fibroblast was studied via overexpression of FatI. The results showed that the proliferation and apoptosis of cultured fetal fibroblast were not affected significantly by the overexpression of FatI using BrdU and TUNEL staining methods, respectively. Moreover, the overexpression of FatI significantly inhibited the senescence of somatic cells compared with enhanced green fluorescent protein (EGFP) transgenic cells (P < 0.01). Quantitative PCR revealed that the mRNA expression of P16 and P53 in the FatI transgenic cell group was significantly lower than that in the EGFP transgenic cell group (P < 0.01). In conclusion, the senescence of goat somatic cells was inhibited by the overexpression of the FatI gene.