A polymer valve and a ventricular assist device using the polymer valve are provided to allow blood to flow in a first direction but prevents blood from flowing backward in a second direction opposite to the first direction. The polymer valve comprises a base body having a hollow therethrough for passing of blood, comprising a pair of support legs formed by cutting opposing sides of an end portion of the base body along an inclined surface toward the center line of the hollow to extend toward the first direction from the body , and a leaflet formed of polymer and attached to the support legs to cover the hollow, wherein the leaflet includes a pair of opposing sides attached to the cutting surfaces of the support legs and an end portion connecting the sides of the leaflet, wherein the leaflet is formed of an opening between the support legs.