The present disclosure discloses a polar code rate matching method and apparatus and a wireless communications device that includes performing sorting processing on the first sequence Z according to a preset rule to determine a second sequence, wherein the first sequence Z is determined based on a Mersenne twister algorithm according to a code length of a target polar code, and interleaving the target polar code according to a mapping function to generate interleaved output bits, wherein the mapping function is determined according to the first sequence Z and the second sequence. A Mersenne twister algorithm is applied to target polar code rate matching such that a bit sequence obtained from the rate matching can be more even in structure, a frame error rate of a punctured polar code can be reduced, hybrid automatic repeat request (HARQ) performance can be improved, and further, communication reliability can be improved.