This essay is focused on the idea of suggesting an alternative fuel for diesel engines. The experiments show that the diesel-biodiesel blends can be used as substitute fuels for diesel engines. Recent studies have demonstrated that the use of diesel biodiesel blends can significantly lower emissions of carbon monoxide (CO), total hydrocarbons (HC), and particulate matter. The mixing of biodiesel with diesel significantly reduces the emission particulate matter (PM) because the blended biodiesel contains oxygen. It was recommended that some alternative fuels that are climate-friendly based on various experiments. There for in the present study these lected biodiesel is jatropha seed oil which was obtained by Trans-esterification process by crude seed oil, because the large availability and easily extract from seed by different process.