Porous carbons were obtained from octafluoronaphthalene defluorinated with sodium metal. When the by-product, NaF was removed with acid solution and the product was treated at 1073 K, the carbon gave a high surface area with mesopores as well as micropores. The coexistence of NaF during heat-treatment of the defluorinated product, however, brought about the formation of pores with a squarish shape.