This presentation shows the chemical reaction involved in preparation of biodiesel (ie. transesterification of long chained fatty acids). Jatropha is the most popular and most suitable oil seed in India for producing Biodiesel. This presentation shows Jatropha availability in India. Further, it also shows the test results of different biodiesel blends on 3100 HP locomotive engine that was performed in Research Designs and Standards Organization(RDSO), Lucknow.