The invention provides a
vena cava filter coated with a macromolecular
coating and a preparation method for the macromolecular
coating. A recycling part, a pre-filtering part, a supporting part, an anti-shifting part and a filtering capturing part are all formed by
cutting a same memory
alloy material through
laser; the filtering capturing part is characterized in that six V-shaped rods stretch out from a closed annular structure in a parallel form, the structure is equally divided by the V-shaped rods and is rotated, and a
branch end is connected with a supporting part, so that a conical netted structure is formed; and the surface
layers of the recycling part, the pre-filtering part, the supporting part, the anti-shifting part and the filtering capturing part are all coated with the macromolecular coatings. A
metal filter provided by the invention adopts the unique hexahedral column structural design, so that the
metal filter has excellent adherence property and is easier to recycle; the endothelialization process after the filter is planted into a
vena cava vessel is effectively slowed down and the internal planting time of the filter is prolonged by the macromolecular
coating; and the difficulty in recycling the filter is relieved and the harm to the
vena cava of a patient caused by a recycling stage is reduced.