The modern meaning of the relationship between the man and the Earth as a classical subject has been discussed in this paper. This paper argues that the recognition about relationship of Man-Earth after 1950's is incorrect in China, because it:(1) was limited by the level of science and (2) limited to economical field.
After 1950's, Larger-scale interaction between human and environment and development problems have suggested a meaning of the relationship, which the centre of relationship is PRED relation, i. e. The relationships between Population, Resources, Environment and Development, so that, theory of PRED co-operation is the key theory of the relationship, and developing models of PRED co-operation is the main direction of modern geography. Five family models are important:(1). population ecological capacity of resources and environment; (2). the environment effection of resource use; (3). the relationship models between development and structure of resource-environment-population in a region; (4).the geopolitical and geoeconomical structure under PRED co-operation and (5) models of regional management. Using these models, ones will develop a theory of relationship of man-earth about basic theory of sustainable development.