In recent years, the liquid lenses are widely used in imaging, biometrics, optoelectronics, and lab-on-a-chip. A liquid lens is successfully developed herein based on the frequency-modulated dielectrophoresis effect. The focal length of the lens is varied by adjusting the output frequency of the input power. The relationships among the frequency, voltage, contact angle, focal length, and lens aperture are obtained. When the applied voltage frequency of the dielectrophoresis lens is varied within 0-20 kHz, the focal length, lens aperture, and lens response time are 6-8 cm, 2-3.25 mm, and about 375 ms, respectively. The as-prepared lens has the advantages of a simple structure, fast driving, precise adjustment, low energy consumption, high resolution, and large dynamic range.