Specimens of pure and Pb-doped high-T-c superconductors Bi2Sr2Ca2Cu3O10 (BSCCO) were irradiated with gamma-rays up to an integrated dose of about 225 MR. The variations of normal state resistance, transition temperature, critical current and lattice parameters with gamma-irradiation were studied. The normal state resistance increases with increase of gamma-dose at zero applied magnetic field, whereas the transition temperature and the critical current decrease with the same gamma-dose. The intensities of the X-ray diffraction peaks of the pure samples decrease with increase of gamma-dose without significant change of diffraction angles or peak widths. BSCCO superconductor is found to be quite sensitive to gamma irradiation but drastic lattice expansion do not occur up to 225 MR. (C) 1997 Academic Press Limited.