Hydrogen is seen as one of energy vector of the next century. Hydrogen, as a renewable energy source provides a potential form sustainable development particular in transportation sector. The hydrogen driven engine reduces both local as well as global emission. Hydrogen gas is in brown color and form of un-separated hydrogen and oxygen generated by the electrolysis process of water by a unique electrode design. Hydrogen gas was used as a supplementary fuel in a petrol engine with few modifications and without need of storage tanks. As hydrogen, Butanol is also used as fuel in engine. Blending of small proportion of petrol and butanol can be used in petrol engine without modification of engine. Using of butanol with petrol improve performance of engine. As hydrogen gas is used as a supplementary and butanol is blend with petrol, it will enhance the combustion characteristics of petrol engine and improve performance. In this project we are going to analyze the performance characteristics of petrol engine with butanol blends using HHO kit. Key Words: Hydrogen, Four stroke petrol engine, Butanol