To prevent great attenuation of a reference signal in a wiring layer emitted from a quartz resonator.

A crystal device 6 includes a substrate 1 having a mount part for a quartz resonator 5 to be mounted thereon and a wiring layer 2 led out from the mount part to an outer surface, the quartz resonator 5 mounted on the mount part of the substrate 1 and having an electrode electrically connected to the wiring layer 2, and a lid member 3 mounted to the substrate 1 for airtightly accommodating the resonator 5. The substrate 1 is an oxide sintered compact containing 10-68 mol% of BaO, 9-50 mol% of SnO2 and 13-72 mol% of B2O3. The wiring layer 2 is made of a metallic material having a specific electric resistance of 2.5 μΩ.cm or less, and the resonator 5 is mounted on the mount part of the substrate 1 via a support member 7 having an elastic modulus of 2.4 GPa or less.