To provide a concrete form lightweight, low in manufacturing cost and easily recycled.

The concrete form comprises a lower main form body 2 and an upper auxiliary form body 3. The main form body 2 is formed by fixing vertical bars 2b, 2b with the upper parts projected upward from a rectangular main template 2a long lengthwise, to both side parts on the back face of the main template 2a and fixing a horizontal bar 2c to the lower end of the main template 2a. The auxiliary form body 3 is formed by fixing a horizontal bar to the upper end on the back face of an auxiliary template 3a equal in width to the main template 2a and shorter in length than the main template 2a. These main form body 2 and auxiliary form body 3 are combined and nailed to form the concrete form 1 made of wood.