To improve our understanding on the unknown sub-vent biosphere, which is the biosphere under seafloor hydrothermal sites, new ideas and techniques for this extreme environment are proposed. Modifications were made to the Benthic Multi-coring System (BMS) which is a tethered submarine rock drill to use its great advantages in approaching and getting uncontaminated samples from the sub-vent biosphere. Besides, drilled boreholes are used for in situ filtering, trapping, and incubation of microbes not only to get valuable information about sub-vent microbial diversity and its functions, but also to acquire novel bio/gene resources. New techniques, which are evaluated and applied to the multidisciplinary science project “Archaean Park”, have proved to be essential for studies of the deep biosphere. A technical assessment indicates that there is no perfect method for getting uncontaminated samples from the deep biosphere, and care should be taken during laboratory handling to minimize the shortcomings of the method. On the other hand, a proper combination of subseafloor sampling and analytical methods will provide us with fascinating clues to the origins of life on the Earth.
