An information adding method and apparatus, to increase a quantity of terminals that can be represented by an identifier sequence. The method includes: performing, by a transmit end, polar code encoding on a first bit sequence to generate an encoded second bit sequence; adding, by the transmit end, a part or all of an identifier sequence to the second bit sequence to generate a third bit sequence, where the identifier sequence is used to identify a terminal; and sending, by the transmit end, the third bit sequence.