The earth is a giant system including the atmosphere, hydrosphere, lithosphere, biosphere, and the mantle, core and planetary space. Earth science is the study on the substance composition, origin, formation, evolution and the interaction of each part of the earth system. In the late 20th century, the earth science developed towards the earth system science, focusing on the lithosphere, and gradually extended to the relationship and interaction with the other layers. Since the 1960s, the International Upper Mantle Program (IUMP), the Mohole Project, the Deep Sea Drilling Project (DSDP) and the Ocean Drilling Program (ODP) were successively implemented in the world, through these projects great progress was made in earth science, confirming the continental drift theory and creating the plate tectonics theory. And the international geoscience community gradually achieved a common view that scientific drilling is the only way to obtain real samples from the deep crust, and a long-term observation station can be established through scientific drilling, which is a telescope and endoscope penetrating into the earth, and is the most important technical method to research on the crustal structure and evolution. At the same time, it will play an important role in detecting the deep biosphere, explaining the mysteries of life evolution and understanding the mechanism of global environmental change. Scientific drilling is not only of important scientific significance, but also of great practical significance for maintaining the man-earth coordination and harmony, and promoting the economic and social development.