This paper deals with the advance of researches in depth geology of South China. Several important conclusions have been derived，including:①The Banxi Complex was not formed by collision in Mesozoic. It is a Weakly metamorphosed sedimentary strata.② The Pt₁-Ar crystallized basement was widely scattered over South China.③The Proterozoic tectonic environment was formed in extension basins near continental margin .The crust may be divided into three layers based on metamorphic facies,and it developed through two stages.