Abstract: There are provided controller control means for receiving acceleration of movement of a housing or an angular speed of rotation of the housing from a controller operated by a user and image generating means for generating a game image obtained by photographing a predetermined direction from a predetermined viewpoint in a three-dimensional game space and for moving the viewpoint when the received acceleration or angular speed exceeds a predetermined threshold value. Alternatively, there are provided controller control means for receiving an angular speed of rotation in a first specific direction of a housing from a controller operated by a user and image generating means for generating a game image obtained by photographing a three-dimensional game space from a predetermined viewpoint and for starting movement to the first specific direction of the viewpoint when the received angular speed exceeds a predetermined threshold value.