The oleander (Thevetiaperuviana) is a potential oil seed and a good alternative protein source for food and animal feeds. The seeds of Yellow oleander from four geographical regions (Busia, Bondo, Thika (JKUAT) and Mombasa districts) in Kenya were subjected to three different studies (physic chemical, nutritional and medicinal). The defatted seed cake was analyzed for nutritional value (proteins, minerals, fibre, moisture and carbohydrates) and ant-nutritional value (Tannins, glycosides, phytates and toxicity). The results showed that the nutritional and anti-nutritional values of these seeds were similar to those of other common oil seeds and depended on the climatic regions. The results showed that the physico-chemical properties of Yellow oleander bio-diesels (flash point, calorific value, viscosity and density) compare well with other plant oil bio-diesels such as soya bean and castor oil and are similar to petroleum diesel. The hexane and ethanol extracts of yellow oleander seeds exhibited moderate to low antibacterial activity. There was no significant difference in biological activity with different regions.