Provided is a pneumatic fender that can be expanded during use to a diameter larger than when the pneumatic fender is not being used, such as during storage, transport, etc. A trunk part (2) is configured by layering a plurality of reinforcing layers (5) between an inner rubber layer (4) and an outer rubber layer (7), cords (6a, 6b) of mutually adjacent layered reinforcing layers (5) intersect and are arranged at a predetermined cord angle (A) in relation to the axial direction, a middle rubber layer (8) is interposed between each of the reinforcing layers (5), the thickness of the middle rubber layer (8) in a neutral, non-expanded state is set to 1 mm to 5 mm, and the cord angle (A) is set to 15 DEG to 45 DEG. Through this configuration, when the inside of the fender (1) is filled with air and given a specified internal pressure, the cord angle (A) increases to an angle of repose while the middle rubber layers (8) undergo shearing deformation, and the trunk part (2) enlarges and expands.