There is provided an image composition apparatus configured to produce a composite image in which a foreground image is overlaid on a part of a background image. The apparatus designates a pair of images used as the background image and the foreground image, when one image of the pair of images is a pictorial image with a certain pictorial style, obtains pictorial style information indicative of the pictorial style of the one image of the pair of images, converts the other image of the pair of images into a pictorial image with the pictorial style indicated by the pictorial style information, produces a composite image from a combination of the pictorial image corresponding to the one image of the pair of images and the pictorial image resulting from the conversion on the other image of the pair of images, and outputs the composite image.