Abstract: Objective: To evaluate the therapeutic values of ultrasound guided PICC catheterization via seldinger menthod. Method: Atotal of 150 patients undergoing ultrasound guided PICC catheterization via improved seldinger menthod was included into observation group, and 150 patients undergoing conventional PICC catheterization were included into control group.Result: The success rate of primary puncture was 99.3%(149/150), success rate of primary implanting was 98.7%(148/150), utilization rate of basilic vein was 95.3%(143/150), and rate of end of the tube at the superior vena cava was 94.7%(142/150) in observation group, and all were significantly increased than those in control group(all P<0.05). The retention time in observation group was (151±17) days and significantly longer than that in control group(P<0.05). The rate of embolism and infection in observation group were significantly lower than those in control group(both P<0.05). There were no significantly difference on bleeding and catheter-related infection between the two groups. Conclusion: Ultrasound guided PICC catheterization under seldinger menthod can significantly increase the success rate of catheterization.