A polar code encoding method and apparatus are provided, the method including obtaining a first sequence used to encode K to-be-encoded bits, where the first sequence comprises sequence numbers of N polar channels, where the sequence numbers of the N polar channels are arranged in the first sequence according to reliability of the N polar channels, where K is a positive integer, where N is a mother code length of a polar code, where N is a positive integer power of 2, and where K≤N, selecting sequence numbers of K polar channels from the first sequence in descending order of the reliability, and placing the to-be-encoded bits according to the selected sequence numbers of the K polar channels, and performing polar code encoding on the to-be-encoded bits.