The invention relates to a data processing apparatus and a data processing method as well as an encoding apparatus and an encoding method which can improve the tolerance to errors. Of an LDPC code which is prescribed in the DVB-S.2 and has a code length of 64,800 and an encoding rate of 2/3, mb code bits are replaced, and the code bits after the replacement become symbol bits of b symbols. When m is 8 and b is 2, where the i+1th bit from the most significant bit of 8 × 2 code bits and 8 × 2 symbol bits of two successive symbols are represented by b i and y i , respectively, replacement of allocating b 0 to y 15 , b 1 to y 7 , b 2 to y 1 , b 3 to y 5 , b 4 to y 6 , b 5 to y 13 , b 6 to y 11 , b 7 to y 9 , b 8 to y 8 , b 9 to y 14 , b 10 to y 12 , b 1 to y 3 , b 12 to y 0 , b 13 to y 10 , b 14 to y 4 and b 15 to y 2 . The present invention can be applied, for example, to a transmission system for transmitting an LDPC code and so forth.
