Abstract: Using the mass-spectrometric method we studied the formation of multi-charged plasma ions during the interaction of laser radiation with solid targets irradiated by neutron beams. We found that structural defects, caused by the neutron irradiation, influence not only the efficiency of the process of material evaporation and emission of plasma, but also the ionization and recombination processes taking place at the initial stage of plasma formation and expansion. We also show the effect of the dose of neutron irradiation on the threshold of plasma formation from the surface of the target.