Abstract: The increasing privatization and commercialization of outer space activities requires us to re-consider the subject of liability arising from cross border infringement stipulated in the current Outer Space Law. The cross border infringement liability arising from private enterprises’ commercial outer space activities which is allowed under International Law is international liability, and the private enterprises and the states are the obvious subjects of liability. The private enterprises should bear the primary liability and limited liability, while the states bear the supplementary liability. Where there are more than one launching state, they should be the joint subjects of liability.