The present technology relates to a transmission method and a reception device capable of ensuring good communication quality in data transmission by using an LDPC code. In group-wise interleaving, an LDPC code with a code length N of 69120 bits is interleaved in units of bit groups of 360 bits. In group-wise deinterleaving, an arrangement of the LDPC code after the group-wise interleaving is returned to an original arrangement. The present technology can be applied, for example, to the case of performing data transmission by using an LDPC code or the like.