The invention provides a construction method of a super high-rise building large movable arm tower crane in-situ converted from inner climbing to outer hanging. A tower body of the tower crane is arranged between an inner wall and an outer wall of a core cylinder through a support beam mechanism; the support beam mechanism includes a support beam structure consisting of two bearing main beams and two bearing secondary beams; and the bearing main beams are fixedly joined with base tooth blocks of a bracket arranged on the outer wall of the core cylinder through beam tooth blocks thereof. The construction method comprises the following steps: a lower support rod is arranged below the support beam mechanism nearest the top end of the outer wall, and is aslant vertically supported between the outer side ends of the bearing main beams and the inner wall; the outer wall shrinks above next support beam mechanism with a lower height; and the steps are repeated until the outer wall totally shrinks. The construction method solves such technical problems as slow reshipment speed and delayed construction period in conversion from inner climbing conditions to outer hanging conditions, achieves convenience for in-situ conversion of the tower crane from inner climbing to outer hanging, and improves the total construction benefit.