A SAW device 11 has an IDT which is provided on the principal surface of a quartz crystal substrate 12 having Euler angles (−1.5°≦φ≦1.5°, 117°≦θ≦142°, 42.79°≦|ψ|≦49.57°) and excites a SAW in a stopband upper end mode, and a pair of reflectors which are arranged on both sides of the IDT. Inter-electrode-finger grooves are recessed between the electrode fingers of the IDT, and inter-conductor-strip grooves are recessed between the conductor strips of the reflectors. The wavelength λ of the SAW and the depth G of the inter-electrode-finger grooves satisfy 0.01λ≦G. An IDT line occupancy η and the depth G of the inter-electrode-finger grooves satisfy a predetermined relational expression. The IDT line occupancy η and a reflector line occupancy ηr satisfy the relationship η