A backlight module, a liquid crystal display and a spliced display device are provided. The backlight module is configured to provide a back light source to the display panel. The backlight module includes a backlight panel. The backlight panel includes a frame and an opening; the opening corresponds to the display area of the display panel. The frame corresponds to the non-display area of the display panel. A first extension portion extends from the first sub-frame in a direction away from opening. In the above manner, the present application is capable of physically reducing the width of the seam between the two adjacent splicing screens by half.