A ultrasonic elliptical vibration cutting (UEVC) technique, as an advanced cutting method, has been successfully applied to machine difficult-to-cut materials for the last decade. In this study, the mechanism of the elliptical vibration locus caused by the “asymmetric structure” on the horn was analyzed theoretically first, and the corresponding relationship between the degree of asymmetry and the elliptical vibration locus was determined based on the finite element method (FEM). Then, an efficient single-excitation UEVC device with “asymmetric structure” was developed and optimized. The resonant frequency of the device was 40.8 kHz, and the amplitude reached 14 µm, which effectively broke the limitation of cutting speed in UEVC. Finally, the UEVC device’s performance was tested, and the advantages in improving the tungsten alloy surface quality and reducing diamond cutting tool wear validated the technical capability and principle of the proposed device.