A method and apparatus for encoding a transport block are provided. The method for encoding the transport block includes: determining, by a transmitter, a size of transport block; dividing, by the transmitter, the transport block into at least one code block based on the size of transport block; interleaving, by the transmitter, the at least one code block by an interleaver; and performing, by the transmitter, a turbo coding for the interleaved at least one code block, wherein the size of transport block is determined based on the number of the divided code blocks.