A rotation input device includes a fixing body having an attachment surface, a rotary body supported by the fixing body in such a manner that the rotary body is rotatable around an axial direction orthogonal to the attachment surface, a rotating electrode attached to the rotary body, a plurality of fixed electrodes attached to the fixing body at respective positions along a circumferential direction around the axial direction, a code plate attached to the rotary body and having a code portion, and a plurality of contact spring portions integrally extending from the respective fixed electrodes and being in elastic contact with the code portion. The contact spring portion extends from an end portion of the fixed electrode in the circumferential direction toward the code portion via a folded portion.