The invention relates to the technical field of building external decoration, in particular to an overhang decorative wire system with light. The overhang decorative wire system with light includes acurtain wall, an installation and detaching mechanism and a connection part; the curtain wall is an external wall enclosure of a building, does not bear weight, and is a lightweight wall body with a decorative effect usually used in modern large and high-rise buildings; the installation and detaching mechanism is arranged on a curtain wall board, one end of the installation and detaching mechanismis fixed in the curtain wall board, the other end of the installation and detaching mechanism is connected with a curtain wall steel keel, the installation and detaching mechanism is used for conveniently and rapidly installing and detaching parts, connected with the curtain wall steel keel, on the curtain wall board, the installation and detaching speed is increased, and the working efficiency is improved; and the connection part is connected with the handling mechanism, the end, away from the curtain wall board, of the connection part is provided with an overhang decorative wire, a base isarranged on the overhang decorative wire and connected with a light device, and the connection part is used for handling the light device. According to the overhang decorative wire system, the connection part is installed rapidly through the handling mechanism and connected with the curtain wall board, and the damage to the curtain wall board is reduced.