Abstract: This invention relates to a safety explosion-sound generating type of bullet for a toy gun, and more particularly one having a cavity formed in a plastic body filled with a material which can produce an explosion-sound effect by collision with a hard object and it is covered by a thin layer. When the body is fired and lands against a hard object, the filling material produces a small explosion, like a sound produced by an actual gun. Furthermore, because the small explosion is produced within a very small bullet (for example, a BB), it is impossible to hurt people.