Photoinduced electron transfer (PET) and enhancement of fluorescence were observed simultaneously for a series of donor-acceptor-type C-60 pearl-necklace polymers, contradicting the conventional notion that the formation of charge-separated state derived from electron transfer (ET) causes the quenching of fluorescence. The quantum yield Phi(f) of the present polymers was one to two orders of magnitude larger than that of the pristine C60. On the other hand, light-induced electron spin resonance (LESR) signals, exhibiting signatures of both the aromatic diamine component cation and the C-60 anion, implied the formation of an ion-radical pair caused by the PET. (C) 2003 Elsevier Science B.V. All rights reserved.