A small screen which enables a player to easily grasp the situation of a game field as well as the positional relationship between the game objects is displayed on a game screen in a game device. A game device which displays on a monitor screen a picture of a game being proceeded in a virtual space by a first object controlled by a player and a second object controlled by a computer comprises a supplementary screen forming means (S210) for forming on the monitor screen a small screen showing the surrounding condition with the first object in the center, a distance calculating means (S202) for calculating the distance between the first object and the second object in the virtual space, and a display magnification setting means (S208) for setting the display magnification on the small screen in correspondence with the distance between the above objects.