A method for supporting a rate-compatible non-binary LDPC code, performed by a wireless device, according to the present embodiment, comprises the steps of: acquiring a kernel part comprising a plurality of first check nodes and a plurality of first variable nodes, the kernel part having a predetermined first code rate applied thereto, and the level of each of the plurality of first variable nodes included in the kernel part being set to 2; and generating, on the basis of the kernel part, a protograph having a second code rate, when a change from the first code rate to the second code rate is required.