A driving belt and method of assembling the same, which can fit rings with elements easily even at a final phase of fitting work. In a driving belt, two rows of endless rings are accommodated and held parallel to each other in a recess of a plurality of elements interlinked annularly in a manner to situate the recess to open to an outer circumferential side and in a manner to pivot with respect to the adjoining elements, and the element includes plural types of elements having different configurations of the recess.