Based on geological and aeromagnetic surveying data, this paper deals syste-matically with some problems concerning geotectonic regionalization and crustalstructure of the Sino-Korean paraplatform, indicating that this paraplatform shouldbe divided into three portions, i. e., North China massif, Baoyin massif and Jiao-liao massif. Adetailed description is made on geological structure of the NorthChina massif with the properties of its two marginal crustal fractures illustrated.It is pointed out for the first time that the Pingdingshan-/wybabsga mega-fracture zone is a mantle-derived ultradeep structure whose eastern and westernsegments are briefly described in such aspecta as their characteristics and theirrole in the evolution of geotectonics and crustal structures.