This paper presents a controllable electrophoresis for assembled single-walled carbon nanotube (SWNT)/polymer transducers under an electric field excitation. The directed assembled high-density SWNT networks are verified with SEM micrograph and Raman spectroscopy. The dynamic electromechanical properties are characterized by a combinative approach of piezoelectric excitation and laser vibrometer measurement. A remarkable performance enhancement for such thin-film transducers in both resonant frequency and quality factor is demonstrated, compared with pure polymer. This observed enhancement can not only be exploited to tailor the thin-film transducers for desired electromechanical properties, but also create versatile and promising pathways for next-generation actuators, sensors, and microsystems with a high performance.