Ultrasonic machining is a new technique, and one of the new and promising processes for machining metals, especially metal alloys with low machinability. In this paper, a set of laboratory studies is used to investigate the effect of using ultrasonic vibrations on the force required for drilling of the thin aluminum workpieces. For this perpuse, three aluminum workpieces with different thicknesses are drilled under three different rotation speeds, and four different advance rates. The results showed that in two aluminum workpieces, 1 and 1.5 mm, the use of ultrasonic vibrations generally reduced the axial force, but in the 2 mm workpiece, it is not possible to understand a meaningfull effect of adding ultrasonic vibrations. In other words, it can be said that adding ultrasonic vibrations with constant amplitude and frequency does not have the same effect on drilling in different conditions, and to reach the most efficient drilling, the characteristics of optimal vibration should be studied.