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Research on the deep sea and deep subsurface environments, the frontier of the Earth, have illustrated a picture of the distinctive biosphere built on the complex chemical, physical, and biological interactions that exist in the vast space. Such research has focused on various aspects of the deep biosphere, including the fluxes of water and light (carbon, nitrogen, etc.) and metallic elements, types and densities of energy for life, the nature of the setting as a habitat for life, the densities and characteristics of life existing there and limits for life in various factors. Understanding these topics has revealed that the deep biosphere is closely related to and plays important roles in the various issues in climate change, management of natural energy and resources, and natural disasters. In addition, when viewing it on a geologic time scale, the researchers have contributed to developing fundamental knowledge in a wide range of fields of science, including the evolution of life isolated from light energy, life-earth coevolution, chemical evolution, evolution of functional biochemical systems, and even the extraterrestrial habitability. This session welcomes presentations about technical, experimental, theoretical, and applied research on the Earth and planetary frontier biosphere, where various factors are complexly interrelated in time and space. We further will discuss the results systematically and multi-dimensionally, which is expected to lead to the future directions of this field of science.