A prediction image generation apparatus for generating a prediction image by performing motion compensation on multiple reference images, the prediction image generation apparatus includes a prediction image generation unit configured to generate the prediction image with reference to a first reference image, a second reference image and a gradient correction term. A motion compensation unit having a motion compensation function using a bi-prediction gradient change (Bi-directional optical flow, BIO) prediction derives the gradient correction term with reference to each pixel value of a horizontal gradient image and a vertical gradient image. An inter-frame-distance weight derivation unit included a gradient correction bi-prediction derivation unit included in the motion compensation unit determines each weight coefficient to be multiplied by the value of the each pixel, depending on a first picture interval and a second picture interval, the first picture interval being a picture interval between a target image to be predicted and the first reference image, the second picture interval being a picture interval between the target image and the second reference image.