A music box is a gift/good the player can give the Miis in Tomodachi Life.
Upon giving a Mii the music box, it says, "Thanks! I'm gonna listen to this right now.", then the scene changes to show them on the floor, happily listening to the music box's song, which plays a slower, higher pitched, music box version of a song heard somewhere else in the game. The box's decoration can be either the island, the Hat Shop, the Food Mart, the Photo Studio, the Compatibility Tester, or the Mii listening to the song. The decoration determines what song is played:
- Island - Island theme, day
- Hat Shop - Hat shop theme
- Food Mart - Food Mart theme
- Photo Studio - Photo Studio theme
- Compatibility Tester - Compatibility Tester theme
- Mii - Mii Maker theme
The song can only play for a certain time. When the music box is winding down, the music slows until it stops; the listening Mii will then be disappointed. The player can tap the "wind up" button to wind the music box back up, and the music resets. This continues endlessly until the player exits.
Upon exiting, the Mii says, "Such a relaxing melody. Doesn't it put you at ease?".
It can also be used during a Fight and it calms the Mii down.