Tuning-fork-type crystal vibrating pieces are disclosed that have a base and a pair of vibrating arms extending from one side of the base in a designated longitudinal direction. A root portion is situated between the vibrating arms, and includes a first taper surface. Extending outboard of the vibrating arms from respective sides of the base are respective supporting arms that extend in the designated direction. Between each supporting arm and the respective vibrating arm is a respective supporting-arm root portion. Each supporting-arm root portion has a second taper surface in the thickness direction of the base.