The present invention relates to a permanent form component. It includes upper plate and peripheral side wall, the above-mentioned upper plate and the peripheral side wall are formed into an open basin-shaped component. It is characterized by that at least more than one of the described upper plate or peripheral side wall is equipped with at least one of wiring box or wire pipe, at least three form components are longitudinally-connected together by means of projecting edge and formed into a group of form components. Said invention can be used for in-situ casting reinforced concrete or prestressed reinforced concrete hollow floor, roof, wall body, foundation bedplate and open-web bridge. Specially, it is used for in-situ casting hollow beamless floor.