Embodiments of the present application provide a method and an apparatus for generating a code word using a Polar code encoding manner. A sequence has N bits, in which K bits are information bits. A matrix of N rows×N columns is used for encoding the sequence. Each row of the matrix has a weight that equals to total number of non-zero elements in the row, and ith row of the matrix corresponds to ith bit position of the sequence, i=1, 2, . . . , N. Each bit position of the N-bit sequence has a reliability. The K bit positions of the sequence that are occupied by the K information bits are selected according to reliabilities of the bit positions of the sequence and weights of the rows of the matrix. The code word is generated by multiplying the sequence with the matrix.