The mass-yield distribution of fission products in the 2.5 GeV bremsstrahlung-induced fission of ^natPb has been measured by using a recoil catcher and an off-line γ-ray spectrometric technique in the 2.5 GeV electron linac at the Pohang Accelerator Laboratory. The determination of mass-yield distribution involves measurement of cumulative yields of 27 fission products and independent yields of 15 fission products in the photo-fission of ^natPb. It was found that the mass-yield distribution of fission products in ^natPb is symmetric with an average mass of 94±0.5 and a full-width at half-maximum of 55±2.0 mass units. The present data along with the literature data in the 50–85MeV bremsstrahlung-induced fission of ^natPb and ²⁰⁹Bi as well as the data at 2.5 GeV for ²⁰⁹Bi show that the average mass of the mass-yield distributions in the bremsstrahlung-induced fission of ^natPb and ²⁰⁹Bi decreases from 102.63 ± 0.51 at 50–85MeV to 94.5±0.5 at 2.5 GeV. The full-width at half-maximum of the mass-yield distribution increases from  about 21.5 ± 1.44 mass units at 50–85MeV to 53 ± 2 mass units at 2.5 GeV. These observations in the 50MeV to 2.5 GeV bremsstrahlung-induced fission of ^natPb and ²⁰⁹Bi have been explained from the point of view of increase in multi-chance fission probability with increasing excitation energy. The role of the fissility parameter (Z₂^F /A_F ) on the full-width at half-maximum is also discussed.