The invention relates to an inner sleeve pipe for a riser pipe. The inner sleeve pipe for the riser pipe comprises an inner sleeve pipe body and a plurality of section steel compositions, wherein the section steel is arranged on the outer wall of the inner sleeve pipe body at intervals in the axial direction, and each section steel composition consists of a plurality of sections of section steel which are fastened and connected in the circumferential direction of the outer wall of the inner sleeve pipe body and are in circumferential array distribution. The inner sleeve pipe has the advantages that six sections of section steel are welded in the circumferential direction of the outer wall of the inner sleeve pipe body in a circular array way, the section steel and an outer layer sleeve pipe or the inner wall of the riser pipe at the outermost layer form surface contact with uniform load distribution, the spoke effect of the section steel is utilized, and the rigidity and the bending-resistant performance of the riser pipe combination are effectively enhanced, so the ice load bearing capability of the riser pipe combination is improved, and the ice-resistant stability of the riser pipe combination is greatly enhanced under the condition without increasing the operation working procedure and the operation time. The section steel per se has excellent cross sectional moment inertia, so the cross sectional moment inertia of the riser pipe is fundamentally improved, and the bending-resistant performance is also greatly improved.