There is now great investment in astronomy as a science in China and other countries. We are currently looking forward to the fruits of the astronomical instruments. Unfortunately the light pollution influences optical/infrared observations on the contrast and the signal-to-noise ratio. Astronomy has been retreated to mountains, deserts and into space. The only way is human being aiming for good lighting environments and protecting the telescope sites. The Commission Internationale de'Eclairage, the International Dark-sky Association, the IAU Commission 21(The Light of the Night Sky) and 50(Protection of Existing and Potential Observatory Sites) have done many efforts in this field to control light pollution. Some countries (Japan, Chile) or local (Tucson, USA; Canarias, Spain) governments have issued guidelines for light pollution to keep dark sky for observatories. These guidelines could be used as references in China. If we do not solve the question of light pollution, the merely a few acceptable observatories in China have to be retreated.