The invention provides a LDPC interpretation method and an encoder based on the matrix splitting on a parity-check matrix. Firstly, the matrix is split; based on the single new matrix after splitting,a check node renewing unit (CNU) and a variable node renewing unit (VNU) are deployed, and a check node renewing calculation and a variable node renewing calculation are arranged, so as to renew check node information and variable node information of the whole original parity-check matrix after intermediate information of each new matrix is calculated respectively, and the above mentioned steps are repeated for iteration until the decoding succeeds or the steps are ended when reaching the maximum iteration times. By adopting the interpretation method and the encoder provided by the inventionto decode the LDPC code, compared with the decoding proposal before the matrix splitting, the scale of the hardware source approximately reduces one third at the same decoding speed when splitting according to a parity method; the decoding speed is approximately increased by one third under the same hardware source.