The harmonics of free electron laser (FEL) were irradiated to the surfaces of compressed C-60 and/or mixture of C-60 and I-2 in the vacuum. After the irradiation of FEL with the typical wavelength, 450 nm or 345 nm, the Raman peak of Ag(2)-derived vibration mode of C-60 shifted to the lower energy side. This result suggested that polymerization reactions of C-60 proceeded. The largest peak shift, ca. 10 cm(-1) was obtained in the mixture powder irradiated by 345 nm irradiation. The decrease of the lattice parameter was confirmed by XRD analyses revealed that inter-molecular combinations took places. Furthermore the change of the crystal structure was closely studied by changing the wavelength of FEL in the range of 350-600 nm. The obtained results demonstrated that three-dimensional polymerization of C-60 was effectively promoted by FEL irradiation and/or especially the effect of the photon-assisted hole-doping from iodine atoms to C-60 molecules.