The internal combustion engine is a rich source of examples of almost every conceivable type of heat transfer. Thereareawide range of temperatures and heat fluxes in the various components of the internal combustion engine. Internal combustionenginescome in many sizes, from small model airplane engines with o 0.25 (6 mm) bore and stroke to large stationary engines witha12"(300mm). About 25 % of the air/fuel mixture energy is converted to work, and the remaining 75% must be transferred fromtheenginetotheenvironment. The heat transfer paths are many, and include many different modes of heat transfer. In this module, we will discuss the heat transfer processes in the engine components, then consider the engine parameters andvariableswhich affect the heat transfer processes. Maximnum amount of heat is transferred târough the cylinder head In this project wehavetafenefforts to analyze the heat transfer through the cylinder head of three cylinder S.I. engine. CAE is extensively used for simulation. Heat transfer is analyzed for different rates of coolant flow and a optimized coolant flow rate is suggested. Keywords: Cylinder Head, Thermal Analyis, Heat Transfer.