A polar encoding method, executed by a transmit end, comprising: obtaining, a reliability sequence of subchannels, and obtaining, at least one subchannel corresponding to at least one shortened bit, wherein numerical values in the reliability sequence are sequence numbers of the subchannels; obtaining a subchannel segmentation point set for the subchannels based on a quasi-period of subchannel polarization, to segment the subchannels; determining a sequence number set corresponding to subchannels in each segment that correspond to a plurality of information bits and a plurality of check frozen bits and that are different from the at least one subchannel corresponding to the at least one shortened bit; determining, for at least one frozen bit, at least one subchannel that is in the subchannels that are different from subchannels corresponding to the plurality of information bits, the plurality of check frozen bits, and the at least one shortened bit, wherein reliabilities of the subchannels corresponding to the plurality of information bits and the plurality of check frozen bits are higher than reliability of the at least one subchannel corresponding to the at least one frozen bit; wherein reliability of at least one subchannel corresponding to at least one of the plurality of check frozen bits is lower than reliabilities of subchannels corresponding to the plurality of information bits; and, reliability of at least one subchannel corresponding to another at least one of the plurality of check frozen bits is higher than reliability of at least one subchannel corresponding to at least one of the plurality of information bits; performing parity check encoding and polar encoding on the plurality of information bits based on subchannels corresponding to the plurality of information bits, the plurality of check frozen bits, and the at least one frozen bit, to obtain encoded information; and sending the encoded information, wherein the plurality of information bits comprises at least one cyclic redundancy check, CRC, bit. obtaining, a reliability sequence of subchannels, and obtaining, at least one subchannel corresponding to at least one shortened bit, wherein numerical values in the reliability sequence are sequence numbers of the subchannels; obtaining a subchannel segmentation point set for the subchannels based on a quasi-period of subchannel polarization, to segment the subchannels; determining a sequence number set corresponding to subchannels in each segment that correspond to a plurality of information bits and a plurality of check frozen bits and that are different from the at least one subchannel corresponding to the at least one shortened bit; determining, for at least one frozen bit, at least one subchannel that is in the subchannels that are different from subchannels corresponding to the plurality of information bits, the plurality of check frozen bits, and the at least one shortened bit, wherein reliabilities of the subchannels corresponding to the plurality of information bits and the plurality of check frozen bits are higher than reliability of the at least one subchannel corresponding to the at least one frozen bit; wherein reliability of at least one subchannel corresponding to at least one of the plurality of check frozen bits is lower than reliabilities of subchannels corresponding to the plurality of information bits; and, reliability of at least one subchannel corresponding to another at least one of the plurality of check frozen bits is higher than reliability of at least one subchannel corresponding to at least one of the plurality of information bits; performing parity check encoding and polar encoding on the plurality of information bits based on subchannels corresponding to the plurality of information bits, the plurality of check frozen bits, and the at least one frozen bit, to obtain encoded information; and sending the encoded information, wherein the plurality of information bits comprises at least one cyclic redundancy check, CRC, bit.