Tapping is a technique commonly employed to make internal threads in the fastening industry. However, sudden breakage of tool bits is the most undesirable event often encountered during thread tapping. In particular, this can most readily occur when making internal threads in blind-holes, especially holes smaller than M6. As such, any effort to prolong the life of the tap is both necessary as well as urgent. The present study tried to use the high frequency vibration generated by a piezoelectric actuator to make threads for the titanium alloy. The thread tapping process was analyzed in detail, involving the Taguchi experimentation method, in which an orthogonal array table, L3(34),was employed to design the experimental runs for use in this study. The effects of interacting processing parameters including the frequency of vibration, vibration amplitude, spindle revolution speed and cutting fluid used on the performance of the tapping process were examined. The result was compared with no ultrasonic-assisted tapping.