The present invention provides a coding method and a coding device. The coding method includes: coding information bits a to be coded via cyclic redundancy check CRC, then inputting the bits coded via the CRC into an interleaver determined by a construction parameter of a Polar code, where the interleaver is configured to interleave the bits coded via the CRC and output interleaved bits; and coding the output interleaved bits via the Polar code to obtain a coded Polar code. The above method is used to solve a problem in the prior art that minimum code distance of a Polar code is not large enough when the Polar code is relatively short or is of a medium length.