This paper presents a controllable electrophoresis allowing a directed deposition of negatively charged single-walled carbon nanotubes (SWNTs) on an electro-active polymer to fabricate thin-film transducers under an electric field excitation. The assembled high-density SWNT networks are verified with SEM micrograph and Raman spectroscopy, and the electric filed-induced mechanism for electrophoresis of SWNT is investigated using electrochemical analysis technique. The dynamic electromechanical properties are characterized by a combinative approach of piezoelectric excitation and laser vibrometer measurement. A remarkable performance enhancement and tunability 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 pathways for variety of applications including polymeric electronic technologies.