PURPOSE: To make a texture dense and defoam completely foams in a mixture by molding the mixture of light-weight aggregate, cement and water into the given shape by means of a centrifugal molding machine.

CONSTITUTION: A drum 7 of a centrifugal molding machine A is rotated, and when the specified number of rotations is obtained, mortar composed of a mixture of light-weight aggregate, cement and water is grouted from an opening in the center of a front end plate 8 into the drum 7, and the rotation of the drum 7 is continued for the specified time. The mortar grouted into the drum 7 is rotated together with the drum 7 to generate centrifugal force to be force fitted into a mold M opened toward the center of the drum by the centrifugal force larger by far than gravity to mold a light-weight concrete formed product L of dense texture. When the molding process is completed, the drum 7 is removed from the centrifugal molding machine A and placed on a bed of a conveying device C, and the drum 7 is disassembled and the mold M is lifted up. Then, the light-weight concrete molded product L having been molded is removed, cured on the bed and finished as a product.