Embodiments of this application provide a polar code rate matching method and apparatus, and a communications apparatus. The rate matching method includes: determining N to-be-encoded bits, where the N to-be-encoded bits include N1 information bits, and both N1 and N are positive integers; encoding the N to-be-encoded bits to obtain N encoded bits; obtaining a first puncturing sequence based on an information bit length N1, the quantity N of the encoded bits, and a quantity Q of to-be-punctured bits; and performing a puncturing operation on the N encoded bits based on the first puncturing sequence to implement a rate matching. To-be-punctured bits indicated in the first puncturing sequence are obtained based on the information bit length N1, the quantity N of the encoded bits, and the quantity Q of the to-be-punctured bits, and are not generated randomly.