Heat sink is an electronic component or a device of an electronic circuit which disperses heat from other components (mainly from the power transistors) of a circuit into the surrounding medium and cools them for improving their performance, reliability and also avoids the premature failure of the components. For the cooling purpose, it incorporates a fan or cooling device. Fins are widely used in heat exchanging devices in automobile radiators, industrial sectors, power plants, newer technology like fuel cells. Generally, the material used for the application of fins are Aluminium alloys. In this work Thermal Properties of fin are numerically investigated using ANSYS Software for different shapes like Circular, Square, Triangular, Hexagonal using Aluminium and Copper composites. Steady state analysis is carried out for different types of fins under the convection and a specified base temperature condition. The length, base thickness, and end thickness of the fins are specified. Thermal conductivity of the fin material is specified. A constant temperature condition is applied at the base of the fin convective boundary conditions applied at the tip of the fin. Comparative study is being done among the fin shapes to find out the best shape under the conditions. Total Heat Flux, steady state temperature distribution is investigated and compared.