Transboundary groundwater resources are the main components of international waters.Special law and regulation must be enacted to adapt the characteristics of transboundary groundwater.A series of pacts on the development of transboundary groundwater resources have gradually formed from the twenties of the 20th century to now.Although the pacts have some positive significance to the development and protection of transboundary groundwater,some defects still exist in them because a series of theoretical problems to work out the legal system on groundwater are not taken seriously.So to make the bilateral or multilateral treaties of using the groundwater fairly and reasonably,to pay attention to the wholeness between the surface water and groundwater and establish special transboundary groundwater management system are the important contents of improving the law about transboundary groundwater resources.