The invention provides a superlift device for a crane and a telescopic boom crane. The superlift device for the crane is used for the telescopic boom crane, and comprises a superlift supporting rod group, a first tensioning device and a second tensioning device, wherein the superlift supporting rod group comprises N superlift supporting rods, N is a natural number of more than or equal to 3, each superlift supporting rod comprises a connecting end and a movable end, and the connecting end is pivoted with a basic arm of the telescopic boom crane; the first tensioning device is connected to the movable end of each superlift supporting rod and is positioned between lifting arms above the telescopic boom; the second tensioning device is connected between the movable end of each superlift supporting rod and the tail of a turntable or the basic arm; and the superlift device for the crane comprises a super-remote lifting mode and a superhigh lifting mode. According to the change of an arrangement mode of pull rope and pull points, the super-remote lifting mode of the traditional crane can be realized, and the superhigh lifting mode which is not owned by the traditional crane can be realized; and moreover, by the superhigh lifting mode, the lifting performance of the telescopic boom crane is greatly improved.