To provide a coffering method having good execution efficiency without using a steel sheet pile.

A plurality of arc-shaped corrugated sheets are connected in the circumferential direction on a barge adjacent to a bridge pier 11, first of all, only one stage of corrugated pipe 18a is constituted, the following one stage of corrugated pipe 18b is constituted in a state to hang up the corrugated pipe 18a with a lifting machine, and then, both pipes 18a and 18b are connected to constitute an outside corrugated pipe 18, for example, consisting of six stages by repeating the procedure mentioned above. For example, an inside corrugated pipe 20 of one stage is constituted so as to oppose it to the inside of the lowest stage section 18f of the outside corrugated pipe 18, and both pipes 18 and 20 are connected with joint members 21 to constitute a partial double cylinder structural body 22. Then, the partial double cylinder structural body 22 on the barge is lowered and is installed on the foundation 13, and then, underwater concrete is placed between the outside corrugated pipe 18 and inside corrugated pipe 20. After the concrete is solidified, water in the outside corrugated pipe 18 is drained.