Abstarct: Omega-3 is the name of a combination of unsaturated, very high chain fatty acids. Plants, especially oily plants, are good sources of Omega-3 production and storage. With true understanding of the synthesized path way of Omega-3 in plants, along with the identification of Omega-3 desaturase co-expressing genes, Plants with a small amount of Omega-3 reserve can be converted into rich Omega-3 resources, by biotechnology efforts. The aim of this study was to find out the Omega-3 desaturase co expressing genes in two plants including soybean (as a representative of oily and di-cotyledon plants) and rice (as a representative of monocotyledon plants) and also this study was done to identify the effects of biotic and abiotic stresses on exxpression patterns of those genes by Bioinformatics tools. Also by completing supplementary studies such as the examining second protein structure of Omega-3 desaturase co-expressing genes in all organisms and drawing their phylogenetic tree along with analyzing the evolution of guanine and cytosine during the evolution of these genes, we can find out more about these genes and how they evolve. The results of evaluating the function of all genes and identifying the closest proteins to them by drawing the protein-protein interaction networks and identifying the peak of the exxpression of genes in developmental stages and tissues showed that, Omega-3 desaturase genes have different performance in both plants. Some of them were gathered at the tip of the branch and the roots. They are effective in plant tip growth. However, the others are present in the stems, leaves and generally in the plant shoots and contribute in responding to biotic and abiotic stresses.