A method for processing a stream of a digital broadcast transmitter, the digital broadcast transmitter, a method of processing a stream of a digital broadcast receiver, and the digital broadcast receiver are provided. The method includes: configuring a stream including a slot to which mobile data is allocated; and encoding and interleaving the configured stream and outputting the encoded and interleaved stream. Each slot of the stream includes signaling data, and the signaling data includes a slot indicator indicating a type of a slot, and may include at least one of a backward training indicator and a forward training indicator according to a value of the slot indicator. Accordingly, information on an adjacent slot is efficiently used.