The continual rise in oil prices, the shortening supply of oil reserves, & the impending threat of global warming due to combustion engine emissions are all reasons to focus on alternatives to energy from fossil fuels. Biodiesel fuel has provided an alternative to diesel oil for over a decade now, & recent research suggests that it will be an even more viable and economical option in years to come. In this book Author has mainly focused on the Transesterification process for extraction of biodiesel form the crude Cotton Seed Oil (CSO). Then conducted an experimental to determine the performance and emission characteristic of the blended Biodiesel in IC engine. The conventional engine was tested for single cylinder at constant rated speed of 1500 rpm throughout its power range using 100% CSO and blends of 20, 40, 60, & 80%. The results found were very impressive, diesel engine performed satisfactorily on biodiesel, & its blends too had better emission properties than diesel. Properties of the 20% blend are very near to diesel fuel & its performance was better than other blends. This book gives huge knowledge for biodiesel production with its performance & emission characteristics.