The fin perforation represents an efficient way to reduce fins weight and enhance its thermal performance. In this study, rectangular plane fins were designed and fabricated aiming to experimentally investigate the effect of the perforation, perforations position and diameter on the solid fins thermal performance under natural convection heat transfer conditions. The experiments were conducted at a wide range of the supplied heat fluxes, and also covered three perforations positions (bottom, middle, top) and perforations diameters (3, 5, 7) mm. At all the used diameters, results showed that the middle position for perforations performed the best in terms of the Nusselt number and mean surface temperature. The maximum Nusselt number and mean surface temperature were 662.08 and 71.95 oC respectively when the heat flux was 4181.82 W/m2, and the perforation diameter was 3.0 mm. The thermal performance of the top-perforated fins was slightly smaller than that of the middle-perforated fins. Besides, the bottom perforated fins demonstrated the worst thermal performance in terms of Nusselt number and the mean surface temperature. Regarding the effect of the perforation diameter, the 3.0 mm showed superior thermal performance compared with 5.0 mm, and 7.0 mm regardless of the perforation’s positions.