The ultrasonic assistant extraction technique of camellia oil was studied with camellia seeds as raw material．The factors affecting the extraction of camellia oil were particle size, ultrasonic time, liquid -solid ratio, ultrasonic temperature as well as ultrasound power．The L16(45) orthogonal test was designed for these factors on the basis of single factor experiments and the optimal extraction conditions were as follows: particle size was 60 screen meshes, ultrasonic time 50 min, liquid -solid ratio 7∶1, ultrasonic temperature 70 ℃, and ultrasound power 130 W. In this case, the average extraction rate of the camellia oil was 19.55％. The operation was simple and rapid with less pollution and cost.