Disclosed is a transmitting apparatus which includes: a packet generator generating a packet including a header and a payload from an input stream including a plurality of transport stream (TS) packets; and a signal processor signal-processing the packet, wherein the header includes a base header including a first field indicating a packet type which is the TS packets, and a second field indicating a number of TS packets included in the payload, wherein the base header further includes a third field set to a first value indicating that there is no additional header or a second value indicating that there is an additional header, wherein, when the third field is set to the second value, the additional header includes a fourth field indicating a number of deleted null packets with respect to each of at least one TS packet group including consecutive TS packets, and wherein the null packets deleted with respect to each of the TS packet group precede a first TS packet or follow a last TS packet included in each of the TS packet group.