A game apparatus, a storage medium and a computer program, suitable to games that can be experienced by a player using an entire body to play a game. The game apparatus comprises: a storage section for storing a predetermined assigned movement for a player; an assigned movement display section for displaying the assigned movement, thereon; a movement detection section for detecting a movement of the player; a player movement display section for displaying the movement of the player detected by the movement detection section, thereon; a similarity decision section for comparing the assigned movement with the movement of the player detected by the movement detection section, to decide a similarity between the assigned movement and the movement of the player; and a game operation section for processing a score on the basis of the similarity decided by the similarity decision section.