Laser damage threshold and damage morphology at the wavelength of 1064 nm are tested in vacuum,air,O2,N2,He2 environments by using 1-on-1 testing method. The results show that compared to normal atmospheric conditions,anti-reflection films(ARF) have a decreasing laser induced damage threshold under vacuum environments. The morphology of the damaged sites showed a particular difference under two conditions. In vacuum environment with a few O2,N2,He2,laser induced damage threshold of anti-reflection films increased. Different gas environments and gas pressure result in different laser induced damage thresholds and damage morphology.