The invention provides a multichannel audio data encoding and/or decoding method. The multichannel audio signal encoding method comprises: encoding a single-track and/or stereophonic audio data; encoding the extended multichannel audio data besides the single-track and/or stereophonic audio data, wherein the extended multichannel audio data may includes type information of the extended channel indicating at least the configuration of an audio channel and be expressed as a channel configuration index. The encoding of the extended multichannel audio data may include: encoding a specified start code indicating the start of the extended multichannel audio data; and encoding the extended audio data by channel. The inventive method is used for more realistic digital multi-media broadcasting and service based on mobile and family cinema.