The domain for the study of earth sciences is wide-extensive, in which one of the major issues in common is the interaction and feedback between Man and Nature.The earth’s crust ranging from the topmost part of the troposphere to the upper part of the lithosphere is a gigantic open and complicated system and is in a condition of nonlinear variations spatially and temporally. It calls for comprehensive studies on both thought of network and mufti-disciplines and, especially, for the integration of the studies on traditional geography with system science, synergism science , the theories of dissipative structure and of self-organizing, with which to look into the Man-Earth System on the earth’s crust and explore new theories and methods as well as new law for the solution of those weight-carrying, urgent and long-range problems such as the global vicissitudes, changes in ecology and environment, the rapid growth of population and the shortage of resources.
    In the earth’s crust, Man-Earth System is the nucleus for studies and has the following four characteristics.
    1.The Man-Earth System is both natural and social in nature;
    2.It is a gigantic open system, having an exchange of material and energy with its outlying surroundings;
    3.Its structures and levels are a network setup;
    4.It is characteristic of time and space.
    All the resources and environments offered by the earth surface are the material base for the development of human society, and the application of modern scientific technologies helps us explore and draw in various ways from the natural world inexhaustible material and energy to satisfy many—sided requirements of human beings in their struggle for existence. However, the more developing the society, the more necessary it should be to maintain a co-existing and harmonious relation with the natural world.In so doing, the Man-Earth System and its regulation will become the most fundamental objective in the study of earth’s crust.