Bone drilling is one of the steps in a typical surgical operation that is performed around the world for reconstruction and repair of the fractured bone. During the last decade, various techniques, such as two-step drilling, ultrasonic-assisted bone drilling and laser drilling, have been introduced to control the level of forces and torque during bone drilling. In this research, rotary ultrasonic bone drilling has been successfully attempted to minimize the forces and torque during bone drilling. The drilling experiments were planned and carried out on pig bones using the design of experiments (response surface methodology). Analysis of variance was carried out to find the effect of process factors such as rotational speed, feed rate, drill diameter and ultrasonic vibrational amplitude on the force and torque. Statistical models were developed for the force and torque with 95% confidential interval, and confirmation experiments have been carried out to validate the models. Microcracks developed during drilling process were characterized by scanning electron microscopy. The results revealed that rotary ultrasonic bone drilling process offered a lower force and torque making it a potential process for bone drilling in orthopedic surgery.