A multi-channel audio signal encoding method includes: obtaining a to-be-encoded first audio frame; obtaining a correlation value set, where the correlation value set includes respective correlation values of a plurality of channel pairs; selecting M correlation values from the correlation value set, where all the M correlation values are greater than correlation values other than the M correlation values in the correlation value set, and all the M correlation values are greater than or equal to a pairing threshold; obtaining M channel pair sets; determining a target channel pair set from the M channel pair sets, where a sum of correlation values of all channel pairs in the target channel pair set is the largest in those of the M channel pair sets; and encoding the first audio frame based on the target channel pair set.