Abstract: The joint device for a tire forming machine comprises a joint device connection frame, composite part laminating device, and cord fabric stitching device, wherein the joint device connection frame axially slides along a portal frame through a connection frame drive device, and is located above the vertical direction of a tire body drum; the composite part laminating device is carried on a joint device connection frame through a composite part frame body; the composite part laminating device comprises an axial laminating drive device and a vertical laminating drive device for controlling and driving a compression roller component located on a composite workstation on the tire body drum; the cord fabric stitching device is carried on the joint device connection frame through a main stitching frame; the cord fabric stitching device comprises an axial stitching drive device and a vertical stitching drive device for controlling and driving a stitching wheel component located on a stitching workstation on the tire