The invention provides a pet music system for providing music and sound effects to pets for influencing, modifying and controlling their mood and behavior. The pet music system of the present invention comprises a portable, lightweight music player, such as an MP3 player, for example, removably attached to the collar of a pet or the halter of a large animal. The music player also incorporates at least one speaker, and a plurality of control buttons for selectively playing a song or sound effect. A pet tunes CD is pre-recorded with a variety of recordings and is transferable to the music player