A thermal-insulated multi-walled pipe for superconducting power transmission comprises: a superconducting cable; a multi-walled pipe composed of a plurality of straight pipes and houses the superconducting cable; and a plurality of spacers that are located between adjacent two straight pipes of the plurality of straight pipes, wherein a cross-sectional shape of each spacer is a polygon having three or more vertices, each spacer has a through-hole at a center in the plane, an inner straight pipe is located to pass through the through-hole, a frictional coefficient μi between each spacer and the inner straight pipe is 0.1 or less, a frictional coefficient μo between each spacer and an outer straight pipe is 0.1 or less, and a ratio Ld/d of a diagonal equivalent length Ld of the polygon to an inner diameter d of the outer straight pipe of the adjacent two straight pipes is 0.9 or less.