An enantiopure helical ferrocene ( Rp)-5 with five ortho-condensed aromatic rings was synthesized using a PtCl2-catalyzed cycloisomerization of planar-chiral 2-ethynyl-1-(4-phenanthrenyl)ferrocene ( Rp)-6f, prepared in 3 steps from known enantiopure sulfinyl ferrocenyl boronic acid ( SS, Sp)-7, as the source of planar chirality. This pentacyclic helical ferrocene showed a very high optical rotation value and strong circular dichroism (CD) signals.