A rotationally-operated electronic component in which a predetermined signal is obtained by rotating a roller-shaped operating dial, and a detent generating mechanism can easily be disposed even when the diameter of the operating dial is reduced. The rotationally-operated electronic component is configured in such a manner that the detent generating mechanism for the operating dial is stored within a recess formed on the left circular portion with coil spring being deflected, and with an urging force of coil spring, movable clicking member is brought into resilient contact with fixed clicking member on the outside thereof. Accordingly, even when the diameter of the operating dial is reduced, the detent generating mechanism can be disposed easily and the preferable detent feeling can be maintained for a long time.