A digital broadcasting system and method of processing data therein are disclosed. According to one embodiment, a digital broadcasting system includes an RS (Reed-Solomon) encoder configured to encode mobile service data for FEC (Forward Error Correction) to build RS frames including the mobile service data and a signaling information table, a signaling encoder configured to encode signaling information including fast information channel (FIC) data, and transmission parameter channel (TPC) data, a group formatter configured to form data groups, wherein at least one of the data groups includes encoded mobile service data, known data sequences, the FIC data and the TPC data, and a transmission unit configured to transmit the broadcast signal including a parade of the data groups.