Abstract: The Qinzhou Bay (Q)-Hangzhou Bay (H) juncture orogenic belt is a giant suture separating Yangzi block from Cathaysian block in South China. It can be divided into three segments, i.e., the northern, the middle and the southern on the basis of the geological variation, separated roughly by the 24° and 27° north latitude. The middle segment is in accordance with the traditional Nanling belt, the northern segment is roughly coincident with the Shaoxing - Jiangshan - Pingxiang zone, and the southern segment is consistent with Yunkai - Shiwandashan Mountainous zone. The southern segment of the Q - H joint orogenic belt is one of the most important topics in studying reworking of the continental crust and mineral prospecting in South China. It is coincident with the whole juncture orogenic belt in geological evolution. The Neoproterozoic massive sulfide deposits occurring at Dajiangping and ophiolite at Xinyi and Luchuan of Yunkai area are direct evidence for existence of an old ocean. More attention should be paid to porphyry copper deposits in future mineral resource prospecting in the study area. These ore deposits are hosted in granitic porphyry which originated from partial melting of the island-arc basaltic rocks associated with subduction of the Proterozoic oceanic plate.