Embodiments of this application provide a method for transmitting encoded information. A communication device obtains K bits of information, and generates a to-be-encoded sequence u1N, wherein N is a length of the sequence. The device encodes the sequence u1N in an encoding process, to obtain an output sequence, and transmits the output sequence. In the sequence u1N, each of the N bits corresponds to a subchannel, and each subchannel has a reliability. The K information bits, a quantity J of first-type auxiliary bits, and a quantity J′ of second-type auxiliary bits are placed in K′=K+J+J′ bit positions of the sequence u1N according to reliabilities of the subchannels. Since the positions of the information bits and the auxiliary bits are pre-determined and not affected by subsequent encoding and rate-matching, overheads of real-time reliability calculation are effectively reduced, time is saved, and delay is reduced.