Method for manufacturing marine concrete structure characterized by introducing a mechanical prestress provided by a prestress material to a mold frame

The object of the present invention is to realize a mold frame to which a mechanical prestress provided by a prestress material is introduced without a large crane vessel for hanging a concrete structure, and having no problems when being used in the sea; and to realize a marine concrete structure that requires no mold frame removing operation since the mold frame is made of concrete and can be used as a surface material of a structure. A method for manufacturing a marine concrete structure is characterized by introducing a mechanical stress provided by a prestress material to a concrete abutment mold frame which serves as an abutment of a side wall portion facing a concrete hollow structure having an opening on at least a part of the upper portion or the side portion, then filling the mold frame with concrete and solidifying it to produce a marine concrete structure.