According to a channel estimation method, a first communication apparatus receives a reference signal, and determines at least two channel vectors based on the reference signal, where the at least two channel vectors include channel vectors s0 and s1. The first communication apparatus receives assistance information for channel estimation from a second communication apparatus, where the assistance information includes channel interpolation parameter information of the channel vectors s0 and s1. The first communication apparatus performs channel estimation based on the channel interpolation parameter information. To prevent degradation in channel estimation performance caused by a receiver's limited ability to calculate a channel interpolation-related parameter in a channel estimation process, a transmitter calculates channel interpolation parameter-related information and sends the channel interpolation parameter-related information to the receiver machine.