The embodiment of the invention provides a generation method and a generation device for a mixed Polar code. The method includes: acquiring an N*N first matrix and a sequence which includes N bits, wherein N is the code length of the mixed Polar code and is a positive integer and N lines of the first matrix are corresponding to the N bits of the sequence and N is an integer; determining the reliability of the N bits and determining the weight of the N lines of the first matrix; according to the reliability of the N bits and the weight of the N lines of the first matrix, selecting K bits in the N bits as information bits or selecting K lines of the first matrix to form a K*N second matrix used coding and coding an information bit sequence according to the positions of the information bits or according to the second matrix so as to generate the mixed Polar code; and K is the length of the to-be-coded information bit sequence and is not larger than N. The generation method and generation device for the mixed polar code not only take the reliability into consideration, but also take the weight of corresponding lines of the first matrix into consideration so that the performance of the Polar code can be improved.