The present application provides a splicing display device, a light-emitting diode (LED) substrate is arranged on adjacent display devices, and the LED substrate covers a gap. LED elements are arranged on a base. A first magnetic member is arranged on the base. A fastening module includes a fastening element and a magnetic assembly. The fastening element is arranged on a support module. At least a portion of the fastening element is arranged corresponding to the gap. The magnetic assembly is arranged on the fastening element and located in the gap. The magnetic assembly is magnetically connected to the first magnetic member.