The objective of present invention is to provide a game input device which allows a player to enjoy the feeling of actually playing a musical instrument along with a rhythm of music, a game method and a game system using such a game input device. The present invention is a game input device having a moving portion and a neck portion, the moving portion has at least two or more inputs, the moving portion is provided onto the neck portion, and the position of the moving portion is movable on the neck portion. The present invention is also a game method and a game system using the game input device.