To provide a wall structural body for building or civil engineering being bendable around a shaft vertical to a plane formed next to columnar members and to provide the columnar member used in it, a manufacturing method for the columnar member, and a small wall structural body used in the wall structural body.

This wall structural body includes the first columnar member 9 having an engaging groove along the longitudinal direction and the second columnar members 10, 11 engaging with the engaging groove. These first and second columnar members are located next to each other, a plurality of them are mutually combined, and a long member 14 is made to pass through a plurality of the first and second columnar members combined together to connect them and constitute this wall structural body. Any of the first and second columnar members is cut while the columnar member having substantially the same cross sectional shape for the longitudinal direction is inclined for shaft axis in the longitudinal direction. By joining these columnar members while being inverted by 180 degrees, this wall structural body is bent around the shaft 104 vertical to the plane 103 formed next to columnar members 9, 10, 11.