PURPOSE: To display the beauty of concrete surfaces, and to rationalize constructing work, by a method wherein the cross section of form surfaces being in contact with concrete is formed in saw-edged shape, the form surfaces are fusion-bonded with resin, and the sizes of an interval between saw-edged apexes neighboring with each other and a recessed depth are individually specified.

CONSTITUTION: The cross section of form surfaces being in contact with concrete is formed in saw-edged shape, an interval between saw-edged apexes neighboring with each other is made at a length of 0.1 to 3.0mm, and a recess in the saw-edged shape is made at a depth of 0.1 to 5.0mm. After that, the form surfaces are fusion-bonded or are coated with resin having water repellency. Thermoplastic resin, such as a tetrafluoroethylene resin and a polypropylene resin, or thermosetting resin such as an epoxy resin is used for coating. In this way, the resin is used in the process of making concrete structures or concrete products, it is made unnecessary that the form is coated with a release agent, and the releasability of the form also can be surely kept.