A digital broadcasting transmission and/or reception system having an improved reception performance and a signal-processing method thereof. A digital broadcasting transmitter comprises a TRS encoder for to TRS-encode a MPEG-2 transmission stream having null data for inserting a Known data and a TRS parity at predetermined positions, randomizer to input and randomize data stream from the TRS encoder, a null packet exchanger to replace the null data for inserting the Known data to the known data, and an encoder for encoding a data streams to which the Known data is inserted. Accordingly, the present invention detects the known data from a signal received from a reception side and uses the detected known data for synchronization and equalization and further uses the TRS parity for correcting error of the received signal, so that the digital broadcasting reception performance can be improved at poor multipath channels.