The invention relates to an automatic 
arterial puncture device and a usage method of the automatic 
arterial puncture device, and belongs to the field of 
medical instruments. The 
system is composed of a B-ultrasonic probe, an automatic puncture instrument and an 
oxygen saturation 
detector. The B-ultrasonic probe, the 
oxygen saturation 
detector and the automatic puncture instrument are connected with a computer. The B-ultrasonic probe is provided with the automatic puncture instrument. The position of an 
artery is judged through two 
modes of the B-ultrasonic probe, wherein one mode is that the position corresponding to the maximum value of pulse sound of pulse beating is selected as an 
artery blood vessel; the other mode is that by pressing through the probe, the 
blood vessel which is not changed in shape as is shown on a screen is an 
artery. The computer recognizes and then positions the artery 
blood vessel, a puncture needle head punctures into the artery blood vessel, blood enters the puncture needle head, 
arterial blood flows into a needle tube, and the 
oxygen saturation 
detector detects whether the blood is 
arterial blood or not. When the level of the 
arterial blood in the special blood gas needle tube stops rising, the needle head is pulled off, and a puncture point is pressed in a pressurized mode to complete the whole puncture process. The whole puncture process is high in efficiency and speed, and obvious effects of improving puncture efficiency and relieving the puncture pain of a patient are achieved.