In a game device, a loading processor loads save data on which user ID information is attached from a storage device 80; an application executing unit executes a game program while using the loaded save data; a game requirement achievement determining unit determines whether or not a predetermined requirement of gameplay is achieved based on a progress status of the game; and item ID acquiring unit acquires an item ID associated with achieved requirement of gameplay; an item acquisition processing unit has a function for generating item acquisition information while using the acquired item ID; and a function limiting unit limits the function of an item acquisition processing unit in accordance with user ID information attached to the save data.