In this paper, we investigate the simulation of natural convection heat transfer of a power electronic component mounted on a heat sink. The heat dissipation is ensured by conduction from the base plate to a heat sink through the fins, and subsequently to the ambient air by convection. This work represents a comparative study of four heat sinks configurations having fins of various profiles adapted for dissipating heat by the use of finite element simulation. The four designs used in our simulation are: two types of parallel plate fins (model 1 and model 2), staggered pin fins which composed of circular and square fins, and a plate fin heat sink with some elliptical pins between plate fins. Each heat sink combination are tested by using Aluminum and Copper materials, and then compared with the Graphite-metal which have an excellent anisotropic thermal conductivity. Besides, the temperature distribution and thermal resistance of these heat sinks are compared and analyzed with a temperature input of 60°C. The objective is to determine the best shape of heat sink with a low mass and low thermal resistance. To select the optimum types of heat sinks, twelve models are compared under the same conditions. As result of our simulation, it is found that the Graphite-metal heat sink provides the lowest thermal resistance versus Copper and Aluminum. Furthermore, it appears that, when pin fins of heatsink are elliptical, the capability of heat dissipation is the best.