An image coding method derives a first candidate having a first motion vector that has been used to code a first block, and derives a second candidate having a second motion vector that has been used to code a second block. It is determined whether a total number of candidates having the first candidate and the second candidate is less than a maximum candidate number, and a third bi-directional candidate is derived when the total number of candidates is less than the maximum candidate number. The third bi-directional candidate has a third motion vector that is identical to the first motion vector, and a fourth motion vector that is identical to the second motion vector. A merging candidate for coding a current block is selected from the candidates having the first candidate, the second candidate, and the third candidate.