The invention discloses a slope rock riverbed steel cofferdam based on suspended corner processing structures. The steel cofferdam comprises a steel cofferdam body and the suspended corner processingstructures distributed on suspended corners of the steel cofferdam body; the steel cofferdam body is a cubic steel jacket box supported on the slope rock riverbed; each suspended corner processing structure comprises two suspended wallboard processing structures; each suspended wallboard processing structure comprises one or more suspended wallboard segment processing structures distributed on thesame vertical plane from front to back; each suspended wallboard segment processing structure is distributed on a suspended wallboard segment; and each suspended wallboard processing structure is aninserting plate type processing structure or a specially-shaped block and inserting plate combined processing structure. The suspended corners of the steel cofferdam is effectively processed through the suspended corner processing structures, the suspended wallboard processing structures in the suspended corner processing structures can adapt to the topographical change of the riverbed and can becombined with bottom blocking structures for underwater blockage, and the problem of the suspended corners of the slope rock surface steel cofferdam can be solved.