The music action game machine comprises: a main body; an operation input device disposed on a front side of the main body so as to be adjacent to hands of a player facing the front side of the main body, the operation input device having a plurality of operation members; a storage device for storing data of a musical composition and data of a performance procedure associated with the musical composition; a music play device for playing the musical composition based on the data stored in the storage device; an operation instructing device for giving the player a visual instruction to operate the operation members in accordance with progress of a play of the musical composition based on the data stored in the storage device; an effect producing device for producing a performance effect in response to a performance operation performed by the player to each of the operation members; an estimation device for estimating the performance operation of the player based on a relationship between the performance procedure defined by the data stored in the storage device and the performance operation of the player; and an estimation informing device for informing the player of an estimation result determined by the estimation device. Therefore, the player can enjoy the simulation of the performance of the music through the operation of the operation members.