In the treatment of thrombotic diseases, extracorporeal ultrasound thrombolysis breaks through the limitations of conventional treatment and in vivo interventional thrombolysis and shows great advantages.However, the ultrasonic transducer used for extracorporeal thrombolysis has low transmitting power and is easily influenced by the environment, which makes it difficult for the ultrasonic signal to reach the lesion area through human tissues and to achieve the destruction of the thrombus structure.In order to solve this problem, a new model of extracorporeal ultrasonic thrombolysis was designed and simulated based on the idea of defective state structure and finite element analysis in this paper.The experimental results show that this structural model can have good acoustic field localization effect and acoustic intensity enhancement effect in the low frequency band part of 10~20 kHz ultrasonic waves, and when the acoustic frequency is rate 14.9 kHz, the structural model has good body penetration effect and has certain possibility to produce structural damage to thrombus in vitro and achieve the effect of thrombus cleaning.These studies are of great importance for the research of efficient and safe in vitro thrombus clearance methods.