A coding method, comprising: obtaining, by a transmit end, to-be-coded information bits; selecting K row vectors from a generator matrix according to a descending order of bit position reliability, and obtain a minimum row weight denoted by W min, of the K row vectors; setting, as frozen bit positions, bit positions corresponding to row vectors whose row weights are less than W min, in the generator matrix, setting, as non-check-required information bit positions, bit positions corresponding to row vectors whose row weights are greater than W min, in the generator matrix, and setting, as to-be-optimized bit positions, bit positions corresponding to row vectors whose row weights are equal to W min, in the generator matrix; constructing a set of candidate check equations based on the to-be-optimized bit positions; performing trial coding on to-be-coded information bits according to each candidate check equation in the set of candidate check equations, and calculating minimum code distances of bit sequences resulting from the trial coding; selecting a candidate check equation corresponding to a largest minimum code distance as an optimal check equation, so as to generate an optimal PC-polar code; performing, by the transmit end, parity check polar PC-polar coding on the to-be-coded information bits based on first constructor parameters, to obtain a coded bit sequence, wherein the first constructor parameters comprise the check equation; wherein the check equation comprises a first element representing a check-required information bit position and a second element representing a check bit position, the first element corresponds to a first vector in a generator matrix for PC-polar codes, the second element corresponds to a second vector in the generator matrix, and the first vector, the second vector, and an addition modulo 2 vector of the first vector and the second vector make true that, if a first Hamming weight of the first vector is the same as a second Hamming weight of the second vector, a third Hamming weight of the addition modulo 2 vector is greater than the first Hamming weight and greater than the second Hamming weight, or if the first Hamming weight is different from the second Hamming weight, the third Hamming weight is greater than a smaller one of the first Hamming weight and the second Hamming weight; and sending, by the transmit end, the coded bit sequence. obtaining, by a transmit end, to-be-coded information bits; selecting K row vectors from a generator matrix according to a descending order of bit position reliability, and obtain a minimum row weight denoted by W min, of the K row vectors; setting, as frozen bit positions, bit positions corresponding to row vectors whose row weights are less than W min, in the generator matrix, setting, as non-check-required information bit positions, bit positions corresponding to row vectors whose row weights are greater than W min, in the generator matrix, and setting, as to-be-optimized bit positions, bit positions corresponding to row vectors whose row weights are equal to W min, in the generator matrix; constructing a set of candidate check equations based on the to-be-optimized bit positions; performing trial coding on to-be-coded information bits according to each candidate check equation in the set of candidate check equations, and calculating minimum code distances of bit sequences resulting from the trial coding; selecting a candidate check equation corresponding to a largest minimum code distance as an optimal check equation, so as to generate an optimal PC-polar code; performing, by the transmit end, parity check polar PC-polar coding on the to-be-coded information bits based on first constructor parameters, to obtain a coded bit sequence, wherein the first constructor parameters comprise the check equation; wherein the check equation comprises a first element representing a check-required information bit position and a second element representing a check bit position, the first element corresponds to a first vector in a generator matrix for PC-polar codes, the second element corresponds to a second vector in the generator matrix, and the first vector, the second vector, and an addition modulo 2 vector of the first vector and the second vector make true that, if a first Hamming weight of the first vector is the same as a second Hamming weight of the second vector, a third Hamming weight of the addition modulo 2 vector is greater than the first Hamming weight and greater than the second Hamming weight, or if the first Hamming weight is different from the second Hamming weight, the third Hamming weight is greater than a smaller one of the first Hamming weight and the second Hamming weight; and sending, by the transmit end, the coded bit sequence.