Most of the oils were extracted through distillation and solvent extraction processes. In this study, the characteristics of oil extraction process from rice bran were evaluated in an optimum operating condition by comparing the ultrasound assisted solvent extraction (UASE) process toe the distillation and the solvent extraction processes. And UASE process was studied in terms of the ultrasonic energy density effects and the extraction yield. Then, the ultrasonic irradiation time was varied as 1, 3, 5, 10, 20 and 30 min and the extraction temperature was set at 293.15, 303.15, and 313.15 K. The ultrasonic power was varied in the range of 390 to 520 W. The energy density was evaluated in terms of the ultrasonic intensity, the ultrasonic irradation effects with the temperature and irradiation time were analyzed. The extraction amount of rice bran oil was increased with ultrasonic irradiation time and ultrasonic power. The irradiation time of ultrasonic extraction process was very shorter than the previous extraction processes. The ultrasonic energy density was proportional to the irradiation power, but the energy density was inversely proportional to the operating temperature.