The present technology relates to a transmission method and a reception device for securing favorable communication quality in data transmission using an LDPC code. In group-wise interleaving, the LDPC code with a code length N of 17280 bits is interleaved in units of 360-bit bit groups 0 to 47. In group-wise deinterleaving, a sequence of the LDPC code after group-wise interleaving is returned to an original sequence. The present technology can be applied, for example, in a case of performing data transmission using an LDPC code, and the like.