A rate matching method for a polar code is provided, to improve performance. The method includes: encoding, based on an N*N encoding matrix of a polar code, a sequence including N first bits, to generate a mother code including N second bits, where the N first bits are in a one-to-one correspondence with N rows in the encoding matrix in sequence, and the N second bits are in a one-to-one correspondence with N columns in the encoding matrix in sequence; determining N−M to-be-punctured second bits from the N second bits, where at least one first bit in N−M first bits participating in encoding of the N−M second bits belongs to the first M first bits in the N first bits, and the N−M first bits are fixed bits; and puncturing the N−M second bits, to obtain a target polar code including M second bits.