Spectroelectrochemistry of [5]radialenes with five 1,3-dithiol-2-ylidenes (DTs) (1) was carried out. The UV-vis-NER spectra of 1(2+) suggest delocalization of two positive charges over three DT units. X-ray structure analysis of an oxygen adduct (2)(2+)(AsF6-)(2)(PhCl)(1.5) reveals that 2(2+) has a cyclopentadienide structure in the central five-membered ring.