The ultrasonic machining is categorized into non-traditional machining process. The machining process using ultrasonic usually applied for brittle materials, but it also capable applied into ductile materials. Wear is the phenomenon in the metal cutting process, two or more surfaces contact definitely causing the worn. This study is to figure out the characteristic the tool life in the ultrasonic machining process. The characteristic of friction and wear of needle pin on disk under the abrasive slurry was observed as comparison. The condition is look like in ultrasonic hole machining, which is using abrasive slurry. 30 mm length of SUS 304 tube with outer Ø 0.5 mm and inner Ø 0.3 mm was used. The other kind of type B SWRS wire pin is used too. 13 gram of Silicon Carbide (SiC) powder dissolved in the 50 gr of water act as lubricant. is the tool life equation for SWRS pin and for SUS 304 pin. During the test, the hydrodynamic lubrication regime was fully developed side by side with the increasing of rotational velocity. The lowest friction coefficient of SWRS pin was achieved at 75 rpm, which the value is 0.00633 and for SUS 304 pin is 0.0064 at 100 rpm. The result of this experiment was reported and discussed.