Abstract: Disclosed is a spring formed from a synthetic resin into one body, including: a plurality of annular members arranged in such a manner as to be coaxial with each other and spaced in parallel to each other; and elastic linkage members for linking the annular members to each other at a plurality of points. In the spring, each of the elastic linkage members is arranged along a virtual cylindrical face formed by the annular members and formed into a lying U-shape curved in the peripheral direction of the annular members; radii of adjacent ones of the annular members are different from each other; and one end portion and the other end portion of each of the elastic linkage members, which portions are respectively linked to the adjacent ones of the annular members, are not overlapped to each other in the axial direction.