A game apparatus includes a CPU, and the CPU generates a game Background Music (BGM) corresponding to a proceeding situation of a game, and etc. The CPU selects data, from a main memory conductor, according to the proceeding of the game, and etc., and generates BGM data regarding one or more track data included in the conductor data. When generating the BGM data, rhythm data, within a rhythm group designated by the track data, is selected in predetermined order or at random, and phrase data, within the same designated phrase group, is selected at random. Then, the BGM data is generated from the selected rhythm data and the phrase data.