Abstract: In the field of laser radiation protection and photoelectric countermeasure,it is important to find out the laser damaged characteristics of photovoltaic detectors.Considering the damaged area and the open circuit voltage,different performance of pulse laser induced damage to photovoltaic detectors in vacuum and atmosphere environments is investigated.The measuring object is uncovered 2CR 10×2.5 four-quadrant silicon photo cell and the irradiation source is 1064nm wavelength pulsed solid-state Nd:YAG laser.In both vacuum and atmosphere,the damage threshold and damage spot appearance of the photovoltaic detector are discussed under single pulse or multi-pulse laser irradiation.The difference of the damage area and their influence on the photovoltaic detector are compared experimentally in both environments.The results show that the laser induced damage threshold in vacuum is obviously lower than that in atmosphere.It is about forty percent of that in atmosphere under the experimental condition.