A method for predictively decoding a motion vector used in motion compensated prediction to restore a video sequence consisting of a temporal sequence of a plurality of frame pictures, comprising: a step of determining a first motion vector predictor candidate that satisfies a predetermined criterion used in determination of motion vector predictor candidates, from a motion vector or motion vectors of one or more partitions belonging to a left-neighboring region located on the left side of a target partition in a frame picture of a decoding target; a step of determining a second motion vector predictor candidate satisfying a predetermined criterion used in determination of motion vector predictor candidates, from a motion vector or motion vectors of one or more partitions belonging to an above-neighboring region located above the target partition; a step of selecting the optimum motion vector predictor specified by the motion vector predictor indication information, from one or more motion vector predictor candidates including at least the first motion vector predictor candidate and the second motion vector predictor candidate; wherein the step of determining the first motion vector predictor candidate comprises scanning a plurality of partitions included in the left-neighboring region using a scan index i, in an upward direction from a bottom of the left-neighboring region, thus determining, a motion vector satisfying the predetermined criterion used in determination of motion vector predictor candidates, as the first motion vector predictor candidate, from the motion vector or motion vectors of said one or more partitions and determining whether or not both the i-th partition and the target partition have the same reference picture list identification number and reference picture identification number, if the i-th partition is present in the scan order in the left-neighboring region and said partition has a motion vector, determining the motion vector of the i-th partition as the first prediction vector candidate, if both the i-th partition and the target partition have the same reference picture list identification number and reference picture identification number. a step of determining a first motion vector predictor candidate that satisfies a predetermined criterion used in determination of motion vector predictor candidates, from a motion vector or motion vectors of one or more partitions belonging to a left-neighboring region located on the left side of a target partition in a frame picture of a decoding target; a step of determining a second motion vector predictor candidate satisfying a predetermined criterion used in determination of motion vector predictor candidates, from a motion vector or motion vectors of one or more partitions belonging to an above-neighboring region located above the target partition; a step of selecting the optimum motion vector predictor specified by the motion vector predictor indication information, from one or more motion vector predictor candidates including at least the first motion vector predictor candidate and the second motion vector predictor candidate; wherein the step of determining the first motion vector predictor candidate comprises scanning a plurality of partitions included in the left-neighboring region using a scan index i, in an upward direction from a bottom of the left-neighboring region, thus determining, a motion vector satisfying the predetermined criterion used in determination of motion vector predictor candidates, as the first motion vector predictor candidate, from the motion vector or motion vectors of said one or more partitions and determining whether or not both the i-th partition and the target partition have the same reference picture list identification number and reference picture identification number, if the i-th partition is present in the scan order in the left-neighboring region and said partition has a motion vector, determining the motion vector of the i-th partition as the first prediction vector candidate, if both the i-th partition and the target partition have the same reference picture list identification number and reference picture identification number.