Biodiesel, a light to dark yellow liquid, is biodegradable, non-toxic and has significantly fewer emissions than petroleum-based diesel. It is practically immiscible with water, has a high boiling point and low vapour pressure. Biodiesel is produced from a wide range of feedstock, including fresh soybean oil, mustard seed oil, waste vegetable oil, palm oil, rapeseed, sunflower, soybean and jatropha, copra, palm, groundnut and cotton seed.In the present years, population of vehicles increased enormously which increases the demand of fossil fuel, The availability of conservative fuels decreased continuously, these reasons makes to find the alternative fuels especially biofuels . The use of biodiesel considerably reduced emission and increase the performance ofthe engine.Now a days researchers have reported the possibility for the production of biodiesel from non edible oil jatropha curcus , pongamia pinnata etc. There is a best source of raw material that is Alexandrian laurel seed oil for biodiesel production. In present study Alexandrian laurel seed oil is used as fuel in C.I engine. The main objective of the present study was to use the non-edible Alexandrian laurel seed oil as biodiesel in ci engine. to reduce the viscosity of neat Alexandrian laurel, transesterification was done to bring it close to that of conventional diesel. In order to obtain a basis for comparison, Various blends are used such as (B10, B20,B30,B100) from this blends B20 shows best results compared to the diesel. Observe the brake thermal efficiency, Brake powder, Break mean effective pressure, Specific fuel consumption at various loads.To improve the performance characteristics Isobutanol additive added in the B20 in the concentration of 10% and 15%. Observe the which blend gives the good result in single cylinder operation based on the result. Finally we conclude that by observing performance, combustion and emission analysis CO, HC, Nox the combination of bio fuel alexandrian laurel seed oil and conventional diesel fuel which one gives better results compared