ESR spectra were observed for both radical anions and cations of C6F6 in rigid solutions. MO calculations followed by computer simulations were performed for these radical ions which were distorted by Jahn-Teller effects. As for the radical anion, INDO calculations for the B-2(1) electronic state resulting from the distortion of the molecular framework to a C-2D symmetry gave simulation spectra satisfactorily fitted to the observed spectrum, while the spectra simulated for one more possible (2)A state due to a D-2 distortion were clearly different from the observed spectrum. Thus, it has been concluded that the radical anion may be in the B-2(1) state. In the case of the radical cation, triplets with a coupling of 13.5 G appeared in either wing region of the spectra observed at low temperatures. Although the MO calculations suggested two possible Du structures in the B-2(2g), state with an elongated ring and in the B-2(3g) state with a compressed ring, the spectra observed for the radical cation were successfully interpreted in terms of the results calculated for only the elongated B-2(2g) state.