The authors developed CMTD (Curved Multi-Tube Device) and studied the system which performed puncture to the liver by machine control.CMTD, which consists of a straight outer needle and a curved inner needle, can revise the error that occurred during puncture. By the system, we detect the puncture angle of the needle during puncture by clicking points of needle on the ultrasound image as a sensor with somascope. We supposed PTCD(percutaneous transhepatic cholangiodrainage) as an environment, and we tested puncture to the silicon tube which simulated a bile duct using this system and studied the effectiveness of this.