Provided is a radio communication device which can always obtain an optimal error ratio characteristic in HARQ using the LDPC code as an error correction code. The device includes: a rearrangement unit (101) which rearranges a transmission bit string according to a column weight of an inspection matrix; an LDPC encoding unit (102) which performs an LDPC encoding based on the inspection matrix on the transmission bit string so as to obtain an LDPC codeword A and performs an LDPC encoding based on the inspection matrix on the bit string subjected to the rearrangement and inputted from the rearrangement unit (101) so as to obtain an LDPC codeword B; and a HARQ unit (103) which selects the LDPC codeword A or the LDPC codeword B in accordance with the number of transmissions of the LDPC codeword.