To provide a lightweight and excellently durable panel for an assembly wall.

The panel for the assembly wall is made of a hardened body of a blend containing at least cement, pozzolanic fine powder, fine aggregate having ≤2 mm particle diameter, a water reducing agent and water. The panel for the assembly wall can contain an inorganic particle having 2,500-30,000 cm2/g Blaine specific surface area which is larger than that of the cement in the blend. The inorganic particle can be composed of an inorganic particle A having 5,000-30,000 cm2/g Blaine specific surface area and an inorganic particle B having 2,500-5,000 cm2/g Blaine specific surface area. The panel for the assembly wall can contain one kind of a fiber selected from the group of organic fibers and carbon fibers in the blend.