Disclosed herein is an image generation device including: a space construction section that constructs a virtual world to be displayed on a head-mounted display; an image generation section that generates, based on a position and a posture of a head of a player wearing the head-mounted display, a display image representing the virtual world in a field of view corresponding to a point of view of the player, and causes the head-mounted display to display the generated display image; and a visitor information acquisition section that acquires information regarding presence of a visitor without a head-mounted display in a space where the player is able to move. While the visitor is present, the space construction section displays an object indicating the presence of the visitor at a corresponding position in the virtual world.