Several important questions regarding the deep continental biosphere remain largely unanswered.

The last two decades have seen extraordinary growth of Geomicrobiology, the interdisciplinary field between Geology and Microbiology. Microorganisms have been studied in numerous extreme environments on Earth, ranging from crystalline rocks from the deep subsurface, hypersaline lakes, to hot springs, and deep-ocean hydrothermal vent systems. This talk will provide a review on global deep biosphere research with an emphasis on China. The talk will start by introducing the history of deep biosphere research in China, e.g., Chinese Continental Scientific Deep Drilling project and then transition to current research activities, e.g., establishment of multi-well deep underground laboratory in eastern China. The talk will then place major results in a global context by presenting continental biomass and diversity estimates in correlation with geological and geochemical conditions.