First, the interval between a left virtual camera and a right virtual camera is determined based on the relative position and the relative orientation of an outer imaging section (left) with respect to a marker, which are calculated from a result of marker recognition in the left real world image, and on the relative position and the relative orientation of an outer imaging section (right) with respect to the marker, which are calculated from a result of marker recognition in the right real world image. After the interval between the left virtual camera and the right virtual camera is determined, the positions and the orientations of the left virtual camera and the right virtual camera are determined based on the determined interval such that the relationship between the position and the orientation of the left virtual camera, and the position and the orientation of the right virtual camera is ideal.