Graphitization of the (111) face of diamond irradiated with fast neutrons under single pulses of the third harmonic of a Ti: sapphire laser (100 fs, 266 nm) is investigated. Transformations of the structure of the graphitized material along the surface of laser spots formed by the pulses at different energies are investigated by confocal Raman spectroscopy. It is found that irradiation of diamond with fast neutrons lowers the graphitization threshold by about five times compared with that of unirradiated diamond.