To improve the workability of a PC panel, its accuracy and the like by a method wherein tiles are arranged in a first form including longitudinal frames and lateral frames so as to place concrete in the first form in order to form PC panel and, after a demolding except the longitudinal frames is executed and then the PC panel is erected and linked to a second form and further concrete is placed in the second form in order to form a horizontal plate.

A first form including longitudinal frames 1 and lateral frames is framed on a plane so as to arrange tiles on the bottom surface part and side surface parts of the first form. Further, two rows of anchoring rebars 7 are disposed upright parallel to the lateral frames. After that, concrete is placed in the first form so as to form a PC panel 9. After that, the first from is demolded except the two longitudinal frames 1. Then, the PC panel 9 is erected vertically so as to link to a second from 11 framed separately. In this case, the anchoring rebars 7 are brought into a state being placed in the second form 11. After that, concrete is placed in the second form 11 so as to form an integral body, in which the horizontal PC panel and the vertical PC panel 9 meet at right angles, in order to form a PC panel having a T-shape section.