In this study, a new type of biodegradable inferior vena cava filter was designed and prepared based on polylactic acid. In addition to having the main functions of a common filter, it is also completely biodegradable in the human body without secondary surgical removal. The changes of surface morphology, molecular weight, viscosity, and radial support strength with degradation time were systematically investigated via degradation experiments in vitro. The results of crimping and expansion tests of the filter showed that reducing the crimping time and increasing the release time make it easier for the filter to recover to its original diameter. Further, the results of a thrombus capture experiment in vitro showed that the thrombus filtration ratio for the filter with double-layer connection structure is 90%. KEYWORDS biodegradable filter, inferior vena cava filter, polylactic acid, thrombus capture experiment