To efficiently connect a precast concrete form.

In the precast concrete form equipped with form forming bodies and the reinforcing rod bodies embedded in the form forming bodies so that at least one side end parts thereof are protruded to the outside, a female connection piece having a fitting recessed part or a male connection piece having a fitting projected part is provided to one side end part of each of the reinforcing rod bodies and both female and male connection pieces are made connectable by fitting the fitting recessed and projected parts in an inside and outside superposed state and the form forming body supporting the male connection piece and the form forming body supporting the female connection, piece are locked in an approaching/spaced-apart direction.