A method for processing signaling data included in at least one protocol layer in an internet protocol (IP)-based digital broadcast transmitter, according to an embodiment of the present invention, comprises the steps of: copying signaling data included in a packet of a layer (N+M) according to a protocol of the layer (N+M); inserting the copied signaling data, a length field for identifying the length of the copied signaling data, and a signaling indicator indicative of the existence of the copied signaling data into the end of a payload of the packet of the layer (N+M), thereby generating the packet of the layer (N+M); generating a packet of a layer (N+L) including a header of the layer (N+L) and the packet of the layer (N+M) according to a protocol of the layer (N+L); generating a packet of a layer (N) including a header of the layer (N) and the packet of the layer (N+L) according to a protocol of the layer (N), wherein the header of the layer (N) includes an indicator field for identifying that the signaling indicator is included in the packet of the layer (N); and processing the packet of the layer (N) according to a protocol of a physical layer, thereby generating a broadcast signal.