Bio-diesel is a renewable diesel fuel substitute that can be made by chemically combining any natural oil or fat with an alcohol. Most European bio-diesel is made from edible oil. In India the above situation does not hold valid because of large scale demand of edible oils for food purposes so non- edible oils are used. Based on the features of the oils form the non edible plants, we have short listed, Jatropha carcus and Pongamia pinnata for further exploitation and extensive studies. The two virgin oils can be used directly in light service CI engine, For application in HSD engines the two oils need modifications so that specifications become closer to that of average HSD. Literature scan of technological aspects of biodiesels show the following gaps in knowledge which calls for further investigations to strengthen this technology. A) Comparative studies of preparation of bio-diesel and detailed characterization. B) Limited studies on blends involving ME of JC & PP with Euro-III & Euro-IV HSD and their characterization. C) Oxidation stability of neat ME and influence of antioxidants on the oxidation behavior of blended esters with petrodiesel.