The Soviet Union successfully launched Sputnik I in 1957 which led to the era of space activities. Although human race has benefited numerous from space activities, unlimited use of outer space has caused pollutions in outer space and consequently at the earth environment. Space debris has become a threat to the security of space activities. Space debris is the most important of these pollutions that, not only creates numerous threats and risks for Orbiting Satellites, It also has harmful effects on earth environment. During drafting UN space treaties, little attention was paid to environmental problems and these treaties did not mentioned of space debris and its hazards. in recent decades, Ethics of Outer Space activities, paid more attention to the environment of outer space and environmental issue of space activities. Therefore, the experiences of environmental law and its preventive policies can be used to reduce the threat of space debris for peaceful space activities and the environment of space and planet Earth.