To provide a mold device for a precast PC plate, by which the production efficiency can be increased.

This mold device 1 comprises a mold 3 and a moving means 4. The mold 3 manufactures concrete plates 6 under a vertically laid state wherein a plurality of concrete plates 6 are erected in such a manner that the plate surfaces may be confronted to each other. The mold 3 is equipped with partition members 3e, 3f, 3f which partition a space between the side frames 3a, 3a into respective forming spaces 7, 7 to form the concrete plates 6, 6. The moving means 4 moves the concrete plates 6, 6 in the direction wherein the end frame 3b, 3b are confronted to each other, together with the mold 3. In the manufacturing of the precast PC plate, the mold device 1 is arranged in a space between stretching based 10, 10 which support stretching materials 2, 2 in such a manner that the direction wherein the end frames 3b, 3b are confronted to each other may meet the confronted direction of the stretching based 10, 10. After laid concrete C1, C2 is hardened, the stretching materials 2, 2 are loosened. At the same time with the loosening, the concrete plates 6, 6 are moved by the moving means 4 in the direction wherein the end frames 3b, 3b are confronted to each other, together with the mold 3.