An electronic device with a connector supporting multiple connection standards includes the connector, a processor, a controller, an EDID (Extended Display Identification Data) ROM, a first multiplexer circuit and a second multiplexer circuit. The first multiplexer circuit is coupled to at least one signal pin of the connector, the processor and the controller. The second multiplexer circuit is coupled to the EDID ROM, the first multiplexer circuit, the processor and the controller. Under an update state, the controller is electrically connected to the EDID ROM through the second multiplexer circuit, and updates EDID in the EDID ROM with update data.