PURPOSE: A foaming mold device is provided to reduce used amount of vapor and cooling water by reducing an internal space according as a back plate is not installed in a movable mold module. CONSTITUTION: A foaming mold device comprises a fixed mold module(10) and a movable mold module(40). The fixed mold module is fixed in a structure. The movable mold module moves toward the fixed mold module. The movable mold module comprises a movable frame(41), moving side plates(44), and a movable plate(46). Both sides of the movable frame are opened. The moving side plates are mounted on one opened side of the movable frame. The movable plate is coupled to the back side of the movable frame and moves the movable frame on which the moving side plates are mounted toward the fixed mold module.
