Lower extremity venous filter implantation has necessary applications in the treatment of a number of diseases. Lower extremity venous filter implantation is a prophylactic measure in which an inferior vena cava filter is implanted into the inferior vena cava, thus preventing the dislodgement of emboli from the inferior vena cava system that can lead to pulmonary embolism. Clinically, it is commonly used in patients with deep vein thrombosis, iliac vein thrombosis, inferior vena cava thrombosis, patients with lower extremity deep vein thrombosis complicating pulmonary embolism if there is a contraindication to anticoagulation, patients at high risk of lower extremity deep vein thrombosis or accompanying pulmonary artery embolism, those with residual thrombus in the deep veins of the lower extremities after surgical or interventional removal of the pulmonary artery embolism, and patients with a large number of thrombus within the iliac-femoral vein or the inferior vena cava, among others. Lower extremity venous filter implantation carries certain risks and may be complicated by displacement of the filter, bleeding, and obstruction of the inferior vena cava, etc. After implantation, patients should follow the doctor’s instructions to carry out the necessary observations and treatments, and if there is a tendency to bleed, they should go to the hospital in a timely manner.