This paper focuses the prediction of the performance of fins having different geometry on a vertical cylinder in natural convection heat transfer. The extensive experimental investigations are performed for different geometrical profile of fins. The hollow cylindrical base having the same fins on their periphery with variable numbers 6 to 18. The temperature measurement was done at different location on the base of cylindrical surface as well as on the surface of the fins. The temperature behaviors for various fins are discussed with power. The measurement was done after justification of the steady state. The temperature is decreases with measurement location from base to tip of fin. As per the variation of base temperature and thermal resistance, semiconvex profile of fin is better than other geometry of fin. The Nusselt number is higher at low power input and less number of fins. The variation in temperature for different power inputs and geometry of fin and the numbers of fin help us to design fins which can be used up in advanced semiconductors in the newest technology because the cooling of those devices is a major challenge to the industries and researchers.