Abstract: [Problem] To more efficiently encode a parameter for intra prediction in an image encoding method whereby a plurality of streams are encoded. [Solution] Provided is an image processing device provided with: a decoding unit that decodes Most Probable Mode information regarding a first prediction unit in a first picture from an encoded stream of the first picture among at least two pictures associated with a scene in common; a first prediction unit that performs intra prediction with respect to the first prediction unit using the Most Probable Mode information decoded by the decoding unit; and a second prediction unit that performs intra prediction using the Most Probable Mode information used by the first prediction unit with respect to a second prediction unit corresponding to the first prediction unit within a second picture among the at least two pictures.