A one-port surface acoustic wave resonator includes a rotated Y-cut LiTaO3 substrate, an interdigital electrode transducer disposed on the LiTaO3 substrate, and reflectors disposed on both sides of the interdigital electrode transducer in the surface acoustic wave propagation direction of the interdigital electrode transducer. When the electrode finger width of the interdigital electrode transducer is denoted by a and the gap between the electrode fingers is denoted by b, the metallization ratio, a/(a+b), is in the range of about 0.55 to about 0.85 and the interdigital electrode transducer is overlapping-length weighted.