Abstract: A hanging decoration structure with a transmission unit includes a casing and a transmission unit. The casing is formed by engaging two hollow hemispheres, and the top of one of the hemispheres has a through hole for passing a hanging element, and the bottom of another hemisphere has at least one through hole, and connectors at both ends of the transmission unit are stored into the casing, and a conducting wire of the transmission unit is passed through the through hole of the other hemisphere, so that the transmission unit can be stored into the hanging decoration to make it easy for users to carry.