Résumé : The rare radiative decay η → π0γγ has been effectively observed and studied at the 70 GeV IHEP accelerator with the hodoscope spectrometer GAMS-2000. The branching ratio for this decay is found to be Br(η → π0γγ) = (9.5 ± 2.3)-10-4. © 1982 Società Italiana di Fisica.