This study presents pioneering experiments utilizing an ultrasonic pulsating water jet (PWJ) for drilling into aluminum alloy 5.5 mm thick following a circular trajectory with a diameter of 6 mm. The innovative approach combines the high frequency of water pulses with frequency of 20 kHz impinging the surface of material at Bernoulli impact speed was 254 m/s to enhance drilling efficiency and observe drilling precision. Circular trajectories with 10, 15 and 20x transition provided basic information on the characterization of the erosion process and the factors entering the process. Finally, an 80x multiple repetition confirmed the complete cutting of the sample and the separation of the core material from the surrounding material. The research provides a foundational understanding of UPWJ technology's potential applications in environmentally clean manufacturing processes.