The utility model relates to a disconnecting link maintenance auxiliary safety tool. The tool comprises a positioning seat, a support connecting rod and a hanging ring. A bottom end of the support connecting rod is fixedly connected with the positioning seat. The hanging ring is fixedly connected to a top end of the support connecting rod. The positioning seat comprises two positioning components and positioning bolts, wherein the positioning components are rotatably connected and can form an accommodation space which closely surrounds a periphery of support groove steel; the positioning bolts are arranged on the positioning components. The positioning bolts comprise a vertical positioning bolt and a transverse positioning bolt. The vertical positioning bolt and the transverse positioning bolt form threaded connection with the positioning components, are extended from an external portion of an accommodation space to an internal portion and abuts against a surface of the support groove steel. An axis of the vertical positioning bolt is vertically arranged. An axis of the transverse positioning bolt is arranged horizontally. The two positioning components are provided with locking mechanisms which are used to lock relative positions of the two positioning components when the two positioning components are closed. By using the tool of the utility model, affiliated security can be brought and safety of a maintainer of high-place operation is guaranteed; working security is increased and the maintainer can be convenient to develop related working.