Method of designing spokes of non-pneumatic tire

Disclosed herein is a method of designing spokes of a non-pneumatic tire which randomly arranges spokes around a circumference to optimize noise dispersion. The method of designing spokes of a non-pneumatic tire includes placing a plurality of spokes (2) holding and supporting a tread (1) to be radially installed around a circumference of the tire on a circular spoke support (3) under the tread (1) to be in contact with the ground, wherein the spokes (2) are arranged at three angles on the circular spoke support (3) around the circumference of the tire, the three angles being divided into a small angle (a), a medium angle (b) and a large angle (c), and the spokes (2) are arranged at irregular angles under a condition that the large angle (c) is greater than the medium angle (b).