An image predictive decoding method comprising: data extraction step for extracting, from compressed data where an image is divided into a plurality of regions and encoded, encoded data of prediction information that is used to produce a prediction signal of a target region, encoded data of partition information identifying a region width of a first partition in a target region, and encoded data of a residual signal; regional information restoration step for restoring the partition information by decoding the encoded data of the partition information; prediction signal production step for, when the restored partition information indicates that the target region is divided into the first partition and a second partition, producing a prediction signal of the first partition from a reconstructed signal by using (i) mode information that specify an inter-picture prediction method, (ii) a reference picture number, and (iii) a motion vector, all of which are included in prediction information associated with a neighbouring region neighbouring the first partition, and producing a prediction signal of the second partition from a reconstructed signal by using restored prediction information from the encoded data of the prediction information associated with the target region; residual signal restoration step for restoring a reproduction residual signal of the target region from the encoded data of the residual signal; signal production step for producing a reproduction signal of the target region based on the prediction signal of the target region and the reproduction residual signal; and storage step for storing the reproduction signal of the target region as the reconstructed signal. data extraction step for extracting, from compressed data where an image is divided into a plurality of regions and encoded, encoded data of prediction information that is used to produce a prediction signal of a target region, encoded data of partition information identifying a region width of a first partition in a target region, and encoded data of a residual signal; regional information restoration step for restoring the partition information by decoding the encoded data of the partition information; prediction signal production step for, when the restored partition information indicates that the target region is divided into the first partition and a second partition, producing a prediction signal of the first partition from a reconstructed signal by using (i) mode information that specify an inter-picture prediction method, (ii) a reference picture number, and (iii) a motion vector, all of which are included in prediction information associated with a neighbouring region neighbouring the first partition, and producing a prediction signal of the second partition from a reconstructed signal by using restored prediction information from the encoded data of the prediction information associated with the target region; residual signal restoration step for restoring a reproduction residual signal of the target region from the encoded data of the residual signal; signal production step for producing a reproduction signal of the target region based on the prediction signal of the target region and the reproduction residual signal; and storage step for storing the reproduction signal of the target region as the reconstructed signal.