The changes of photoelectronic characteristics for photodevices and MOS capacitors after proton or Υ- ray irradiation are investigated. The annealing effect of the samples at 150℃ and 200℃ after Υ- ray irradiation is also discussed. The photocurrent spectra of the Si photodevices measured with spectrophotometry in the range of Si spectral response have been used to understand the space distribution of damages in the devices induced by different irradiations.