An image encoding method according to an aspect of the present invention includes: generating, from a plurality of first sub-bitstreams which are obtained by encoding a plurality of images on a per layer basis according to spatial scalable image encoding, a second sub-bitstream including two or more first sub-bitstreams corresponding to two or more layers, the two or more first sub-bitstreams being included in the plurality of first sub-bitstreams; and generating a descriptor including a first field indicating a minimum value for two or more layer identifiers indicating the two or more layers and a second field indicating a maximum value for the two or more layer identifiers.