A touch display substrate is provided, including a central touch area and a routing area located around the central touch area, where the routing area is provided with isolation lines and a plurality of touch signal lines led out from the central touch area, the extension direction of the isolation lines is parallel to the extension direction of the touch signal lines, the touch signal lines include first touch signal lines arranged close to the isolation lines and second touch signal lines arranged far from the isolation lines, and the width of the first touch signal lines is greater than the width of the second touch signal lines. A touch display device and a touch control signal line distribution method are provided.