To provide an image coding device having high coding efficiency and an image decoding device. A plurality of prediction procedures that uses various types of correlations between pixels are adaptively applied with a coded signal as a reference. With respect to an input pixel, first residual and prediction information are obtained by a first prediction unit that carries out in-screen prediction and the like, second residual and prediction information are obtained by a second prediction unit for predicting a first residual as a serial additional process, and third residual and prediction information are obtained by a third prediction unit for directly predicting a pixel to be coded as a parallel additional process on the input pixel. Which of either the second residual or the third residual to code is determined based on the coding cost, and the signal is switched in the first switching unit.