PURPOSE: To achieve usage of a column formwork and a beam formwork in common, achieve coping with change of sectional size of each formwork and length of a building frame, and facilitate molding the formwork.

CONSTITUTION: A precast concrete formwork forming a column formwork P and a beam formwork Q is composed of corner bodies 1 disposed at a corner position of the formwork and plate wall surface bodies 2 connected along the side edges of the length of the corner bodies 1. The corner body 1 has a cut connection side edge 1A of which length side edge is to be engaged with the length side edge of the wall surface body 2, and a fixing protrusion 1B to be embedded in post-placed concrete is protruded on the inner side of the corner body 1. The corner body 1 and the wall surface body 2 are worked by extrusion molding of precast concrete formed long.