An image decoding method for decoding an image using plural intra prediction modes, including decoding first binary data and second binary data, the first binary data indicating a first intra prediction mode to decode the image, the second binary data indicating a second intra prediction mode to decode the image, wherein in the decoding, coded data is obtained which includes a first context adaptive segment, a second context adaptive segment, a first bypass segment, and a second bypass segment. The first context adaptive segment and the second context adaptive segment are decoded by context adaptive binary arithmetic decoding which is arithmetic decoding using a variable probability updated based on decoded data, and the first bypass segment and the second bypass segment are decoded by bypass decoding which is arithmetic decoding using a predetermined fixed probability.