Rear floor structure for vehicles

In a rear floor structure of a vehicle body wherein a rear floor panel (1) has raised parts (2) on either side thereof that protrudes upwards and a recessed part (3) between the raised parts (2) for providing a storage space, a rear floor cross member (6) is disposed in a front end portion of the recessed part (3) such as to bridge the recessed part transversely, and one or both of a locking metal member (7) for securing a child safety seat to the vehicle body and a rear seat back centre hinge (8) is/are attached on the rear floor cross member (6).