The present invention provides an image coding method and an image decoding method by which an image can be restored correctly even if part of memory management information is lost by a transmission channel error, a candidate of a reference image that can be referred to is selected more appropriately, and coding efficiency is improved.The image coding method includes a step for executing coding of an image (Step 100), a step for judging whether a picture in the memory which is never used as reference exists (Step 102), a step for coding memory management information for releasing the picture in the memory which is never used as reference when a picture in the memory which is never used as reference exists (Step 103), a step for releasing the picture in the memory which is never used as reference (Step 104), a step for judging whether the memory management information that releases the picture in the memory which is never used as reference is coded by coding of an image immediately before (Step 105), and a step for coding again the memory management information that releases the picture in the memory which is never used as reference when the memory management information is coded (Step 106).