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The Ediacaran organic-rich Doushantuo Shale in the Yichang area of the Middle Yangtze Platform has attracted significant attention, although few studies have focused on the methane adsorption capacities of this new shale. Hence, geochemical and mineralogical analyses, focused ion beam-scanning electron microscopy, and high-pressure (up to 32 MPa) methane adsorption analyses of the Doushantuo Shale selected from the Yichang area were investigated to clarify its nanopore characteristics, methane adsorption capacity, and influencing factors. Our results provide critical new insights into the kerogen and bitumen pore characteristics and methane adsorption capacity of this new shale. Kerogen, bitumen, and inorganic minerals have their own pore development characteristics, which have been observed from SEM images. The large-scale kerogen particles exhibited alignment with elongated shapes with relatively small organic matter (OM) pores or no visible OM pores; however, the bitumen particles have abundant elliptic-like OM pores with a complex structure. The calculated maximum absolute adsorption amounts ranged from 0.70 to 6.58 m3/t and from 0.69 to 5.27 m3/t, respectively, using the supercritical Dubinin-Radushkevich and Langmuir models, which were smaller than those of the Ordovician-Silurian Wufeng-Longmaxi and some typical North America Shales. The influencing factors included pore structure, total organic carbon (TOC) content, OM characteristics, and clay minerals. Moreover, TOC content and OM characteristics predominate on the methane adsorption capacity followed by pore structures, clay minerals, and other factors.