Triamcinolone acetonide (TA) is a corticosteroid that is used in the systemic and topical treatment of many inflammatory diseases. In this study, a phonophoretic drug delivery system was designed to enhanced the TA permeability and the influence of ultrasound was examined. In order to establish the transdermal delivery system for TA, a hydrophilic carbopol gel containing TA was prepared after adopting phonophoresis. A permeation study treatment was carried out for 10 h. The level of TA permation through the skin was evaluated under various ultrasound conditions including the frequency (1.0, 3.0 MHz), intensity (1.0, 2.5 W/cm2), and duty cycle (continuous, pulse mode) using a 0.5% TA gel. The highest permeation was observed under the ultrasound treatment conditions of low frequency, high intensity, and in continuous mode.